Michael L. Morris DETERMINING COMPARATIVE ADVANTAGE THROUGH DRC ANALYSIS guidelines emerging from CIMMYT's experience CIMMYT is an internationally funded, nonprofit scientific research and training organization. Headquartered in Mexico, the Center is engaged in a worldwide research program for maize, wheat, and triticale, with emphasis on improving the productivity of agricultural resources in developing countries. It is one of 13 nonprofit international agricultural research and training centers supported by the Consultative Group on International Agricultural Research (CGIAR), which is sponsored by the Food and Agricultural Organization (FAO) of the United Nations, the International Bank for Reconstruction and Development (World Bank), and the United Nations Development Programme (UNDP). The CGIAR consists of a combination of 40 donor countries, international and regional organizations, and private foundations. CIMMYT receives core support through the CGIAR from a number of sources, including the international aid agencies of Australia, Austria, Brazil, Canada, China, Denmark, the Federal Republic of Germany, Finland, France, India, Ireland, Italy, Japan, Mexico, the Netherlands, Norway, the Philippines, Spain, Switzerland, the United Kingdom, and the USA, and from the European Economic Commission, Ford Foundation, Inter-American Development Bank, OPEC Fund for International Development, UNDP, and World Bank. CIMMYT also receives non-CGIAR extra-core support from Belgium,the International Development Research Centre, the Rockefeller Foundation, and many of the core donors listed above. Correct Citation: Morris, M.L. 1990. Determining Comparative Advantage Through DRC Analysis: Guidelines Emerging from CIMMYT's Experience. CIMMYT Economics Paper NO.1. Mexico, D.F.: CIMMYT. ISSN - 0188 - 2414 Contents Abstract Acknowledgements Preface V VI vii 1 INTRODUCTION 1 2 A SIMPLE EXAMPLE OF COMPARATIVE ADVANTAGE 3 3 REVIEW OF THE DOMESTIC RESOURCE COST METHODOLOGY 6 6 Step 1: Developing Enterprise Budgets Step 2: Classifying Inputs and Outputs 7 Step 3: Determining Market Prices and Social Prices 7 Step 4: Calculating Net Social Profitability 12 14 Step 5: Calculating Resource Cost Ratios Step 6: Conducting Sensitivity Analysis 16 4 USES OF DOMESTIC RESOURCE COST ANALYSIS Revealing Distorting Effects of Government Policies Revealing Comparative Advantage Between Enterprises Revealing Comparative Advantage Between Regions Revealing Comparative Advantage Between Technologies Setting Agricultural Research Priorities 5 6 19 19 22 24 25 27 PROBLEMS COMMONLY ENCOUNTERED IN USING DRC METHODS Extensive Data Requirements Determining Social Prices for Primary Factors Determining Social Prices for Non-traded Tradables Estimating an Equilibrium Exchange Rate Predicting General-Equilibrium Effects Comparative Advantage vs. Competitive Advantage 28 28 29 31 33 LESSONS FROM THE CIMMYT CASE STUDIES 36 References 34 35 41 Tables and Figures Table 1. Production conditions in two potential trading partners 3 Table 2. Net welfare gains achieved through specialization and trade 4 Table 3. Establishing social prices for fertilizer at the farm level, Nakuru area, Kenya, 1987 9 Table 4. Establishing social prices for non-standard tradable inputs at the farm level, Nakuru area, Kenya, 1987 11 Enterprise budgets for irrigated crops in Zimbabwe, 1986 (Z$lha) 13 Table 6. Resource cost ratios for irrigated crops in Zimbabwe, 1986 15 Table 7. Interpretation of resource cost ratios (RCRs) 16 Table 8. Social profitability of rainfed wheat in Zimbabwe under four yield levels, 1986 17 Table 9. Measures of comparative advantage and policy incentives 20 Table 10. Sources of difference between private and social profitability of irrigated crops in Zimbabwe, 1987 21 Resource cost ratios for competing enterprises in Ecuador, 1983 23 Resource cost ratios for two wheat-producing regions in Mexico, 1985 25 Social profitability of wheat production technologies by size of field, Kenya, 1987 26 Figure 1. Conditions giving rise to a non-traded tradable 32 Figure 2. Establishing social prices for non-traded tradables 32 Figure 3. Using DRC analysis for research resource allocation 37 Table 5. Table 11. Table 12. Table 13. Abstract Knowledge of comparative advantage is important for developing countries, because potential welfare gains from specialization and trade can be used to foster economic growth. One practical difficulty with using comparative advantage for designing agricultural policies or allocating research resources is that comparative advantage is difficult to determine empirically. The domestic resource cost (DRC) framework of analysis offers a way of empirically measuring comparative advantage by generating quantitative indicators of the efficiency of using domestic resources to produce a given commodity, as measured against the possibilities of trade. These quantitative indicators provide an empirical measure of comparative advantage. At the same time, the analytical framework allows the distortionary effects of government policies to be measured. The paper first describes the basic DRC methodology, using examples drawn from a series of case studies carried out over the past five years by the CIMMYT Economics Program. This step-by-step description of the DRC methodology is a concise, non-technical guide for use in conducting applied comparative advantage studies and addresses a number of practical and conceptual problems commonly encountered. The paper then summarizes a number of lessons learned over the years at CIMMYT and evaluates the usefulness of the DRC framework as a tool for applied policy analysis and research resource allocation. v Acknowledgements Acknowledgements This Thispaper paperdescribes describestheoretical theoreticaland andpractical practicallessons lessonsemerging emergingfrom fromaaseries seriesofof comparative advantagestudies studiescarried carriedout outduring duringthe themid-1980s mid-1980sby byeconomists economists comparativeadvantage from theInternational InternationalMaize Maizeand andWheat WheatImprovement ImprovementCenter Center(CIMMYT), (CIMMYT),inin fromthe collaboration collaborationwith with colleagues colleaguesininnational nationalagricultural agriculturalresearch researchprograms. programs. Without Withoutthese thesestudies, studies,ititobviously obviouslywould wouldhave havebeen beenimpossible impossibletotowrite writeaa summary summarypaper paperdetailing detailingshared sharedexperiences. experiences.Therefore, Therefore,the theother otherauthors authorsofof the theoriginal originalcomparative comparativeadvantage advantagestudies studiesalso alsodeserve deservecredit creditfor forthe thepresent present document: document:Derek DerekByerlee, Byerlee,Jim JimLongmire, Longmire,and andLarry LarryHarrington HarringtonofofCIMMYT; CIMMYT; Sutat SutatSat-thaporn Sat-thapornofofthe theMinistry MinistryofofAgriculture, Agriculture,Thailand; Thailand;and andJuma JumaLugogo Lugogo ofofEgerton EgertonUniversity, University,Kenya. Kenya. InInaddition, addition,several severalindividuals individualscontributed contributedby bypreparing preparingmaterials materialsfor foraa workshop titled"Research "ResearchResource ResourceAllocation Allocationand andComparative ComparativeAdvantage," Advantage," workshoptitled sponsored sponsoredjointly jointlyby byCIMMYT CIMMYTand andby bythe theRegional RegionalCoordination CoordinationCentre Centrefor for Research Researchand andDevelopment DevelopmentofofCoarse CoarseGrains, Grains,Pulses, Pulses,Roots, Roots,and andTubers Tubers (CGPRT), heldininBogor, Bogor,Indonesia, Indonesia,during duringOctober-November October-November1987. 1987.These These (CGPRT),held included JimLongmire, Longmire,Larry LarryHarrington, Harrington,Juan JuanCarlos CarlosMartinez, Martinez,and andBeatriz Beatriz includedJim Avalos PearsonofofStanford Stanford AvalosofCIMMYT; ofCIMMYT;Govert GovertGijsbers GijsbersofCGPRT; ofCGPRT;Scott ScottPearson University; University;Mathias Mathiasvon vonOppen Oppenofofthe theUniversity UniversityofofHohenheim, Hohenheim,Germany; Germany;and and Klaus KlausAltemeier, Altemeier,consultant. consultant. Derek DerekByerlee, Byerlee,Robert RobertTripp, Tripp,Larry LarryHarrington, Harrington,John JohnBrennan, Brennan,Mitch MitchRenkow, Renkow, and andJim JimLongmire Longmireofofthe theCIMMYT CIMMYTEconomics EconomicsProgram Programmade madedetailed detailedcomcomments mentson onearly earlydrafts draftsofofthe themanuscript. manuscript.Special Specialthanks thanksalso alsogo gototoLynn LynnSalinSalinger Associatesfor forInternational InternationalResources Resourcesand andDevelopment Development(AIRD), (AIRD),who who gerofofAssociates served externalreviewer reviewerand andprovided providednumerous numeroushelpful helpfulsuggestions. suggestions.Kelly Kelly servedasasexternal Cassaday Cassadayand andMike MikeListman Listmancontributed contributededitorial editorialservices, services,Miguel MiguelMellado MelladoE.E., , Manuel ManuelFouilloux Fouillouxand andEfren EfrenDiaz DiazChias Chiasassisted assistedwith withthe thelayout layoutand andfigures, figures, and andRocio RocioVargas VargasGranados Granadosprepared preparedthe thetables. tables. VI VI Preface This paper is the first in a new series, the CIMMYT Economics Program Papers. This series is intended to report more substantive research results generated by the staff of the CIMMYT Economics Program and collaborators in national agricultural research systems. Each CIMMYT Economics Program Paper is reviewed by one or more independent external referees prior to publication. This initial paper summarizes some of the lessons learned during the past few years by CIMMYT economists while carrying out a series of applied comparative advantage studies based on the domestic resource cost (DRC) methodology. Applied macro-level policy analysis represents something of a change from the CIMMYT Economics Program's traditional micro-level emphasis on technology evaluation through on-farm research methods. However, our efforts to examine comparative advantage issues relating to wheat received an enthusiastic response from collaborators in the national systems, many of whom have requested materials to explain and clarify the methodology. This paper attempts to respond to this demand by generating resource materials that can be used in planning and conducting applied comparative advantage work. We hope the paper will prove useful to our colleagues in the national agricultural research systems who wish to design studies to generate the kind of empirical information which so often is missing from the policy debate. Derek Byerlee Director, Economics Program VII r 1 Introduction Knowledge of comparative advantage is important for developing countries, because potential welfare gains from specialization and trade can be used to foster economic growth. National income often can be increased through policies encouraging farmers to produce commodities that exploit existing patterns of comparative advantage. Over the longer run, additional welfare gains can be assured if research resources are used to strengthen comparative advantage in the future. This suggests that agricultural policies and research resource allocation decisions should be based at least in part on comparative advantage considerations. Recent developments in the global economy indicate that agricultural policy makers have indeed started to pay increased attention to comparative advantage. During the 1980s, many countries have implemented policy reforms designed to reduce state participation in agriculture, increase productivity, liberalize commodity trade, and free up market prices to playa greater role in directing economic activity along efficiency lines. At the same time, increased pressure has been put on research administrators to ensure the cost-effectiveness of agricultural research expenditures. Significantly, these developments have occurred in industrialized as well as developing countries, both market economies as well as centrally planned economies. Unfortunately, one practical difficulty with using comparative advantage for designing agricultural policies or allocating research resources is that comparative advantage is not easy to determine empirically. Simply comparing production costs between two regions or countries is often inconclusive, because comparative advantage is not directly related to absolute production costs. Even if relative production costs are known, frequently these are distorted by government policies or market failures. Policy makers and research administrators thus require a way to "see through" market distortions in order to determine true underlying patterns of comparative advantage. This paper evaluates one method for empirically determining comparative advantage. The domestic resource cost (DRC) framework generates quantitative indicators of the efficiency of using domestic resources to produce a given commodity, as measured against the possibilities of trade. These quantitative indicators provide an empirical measure of comparative advantage. At the of the distortionsame time, the analytical framework also allows measurement ofthe ary effects of government policies. The paper first describes the basic DRC methodology, using examples drawn from a series of case studies carried out over the past five years by the CIMMYT Economics Program. This step-by-step description of the DRC methodology provides a concise, non-technical guide for use in carrying out applied comparative advantage studies and addresses several practical and conceptual problems commonly encountered. The paper then summarizes a number oflessons learned over the years at CIMMYT and evaluates the usefulness of the DRC framework as a tool for applied policy analysis and research resource allocation. CIMMYT's CIMMYT'sinterest interestinincomparative comparativeadvantage advantagework workoriginally originallygrew grewout outofofthe the desire desiretotodevelop developanalytical analyticaltools toolsfor foruse usebybyresearch researchadministrators administratorsininnational national agricultural agriculturalresearch researchsystems systems(Longmire (Longmireand andWinkelmann Winkelmann1985). 1985).InInananera eraofof shrinking shrinkingresearch researchbudgets, budgets,these theseadministrators administratorswere werelooking lookingfor forways waystoto increase increasethe thecost-effectiveness cost-effectivenessofofresearch researchexpenditures. expenditures.Empirical Empiricalknowledge knowledge ofofa acountry's country'spattern patternofofcomparative comparativeadvantage advantagepresumably presumablywould wouldhelp helpimimprove provethe theallocation allocationofofscarce scarceresearch researchresources. resources.CIMMYT CIMMYTeconomists, economists,somesometimes timesworking workinginincollaboration collaborationwith withlocal localresearchers, researchers,carried carriedout outa aseries seriesofof case studiesbased basedtotovarious variousdegrees degreesononDRC DRCmethods. methods.These Thesestudies, studies,most mostofof casestudies which whichfocused focusedononthe theefficiency efficiencyofofwheat wheatproduction productionininnon-traditional non-traditionalenvironenvironments, ments,were werecarried carriedout outininThailand Thailand(Harrington (Harringtonand andSat-thaporn Sat-thaporn1984), 1984),inin Ecuador Ecuador(Byerlee (Byerlee1985), 1985),ininMexico Mexico(Byerlee (Byerleeand andLongmire Longmire1986), 1986),ininZimbabwe Zimbabwe (Morris (Morris1988a), 1988a),and andininKenya Kenya(Longmire (Longmireand andLugogo Lugogo1989). 1989). 22 2 A Simple Example of Comparative Advantage The theory of comparative advantage is generally attributed to Ricardo (1817), who first extended the optimization principle defining efficient choice of output by firms into the arena of international trade. Ricardo pointed out that a country can achieve net welfare gains by concentrating productive capacity on goods and services of which it is a relatively efficient producer and importing the rest. Significantly, and somewhat counter-intuitively, the country need not be the lowest cost producer of a given product (Le., the most efficient in absolute terms) in order to have a comparative advantage in its production. The principle of comparative advantage is perhaps best illustrated through a simple numerical example (Table 1). Assume the world consists of only two countries, Alpha and Beta, which produce two commodities, wheat and textiles, using a single homogeneous factor of production, labor. This means that the value of each product is determined exclusively by its labor content. Now assume that one unit oflabor in Alpha produces 6 t of wheat or 2 t of textiles, while one unit of labor in Beta produces 2 t of wheat or 1 t of textiles. (The differences in productivity between Alpha and Beta result from differences in technology and resource endowments.) Clearly, Alpha is absolutely more efficient in the production of both commodities, since Alpha can produce both wheat and textiles at lower per-unit costs than Beta. However, this does not imply that Alpha should produce both wheat and textiles and Beta should produce nothing. With open economies, both Alpha and Beta can achieve net welfare gains through specialization and trade. To see this, it is necessary to consider the relative efficiency of production within each country. In absolute terms, Alpha may be more efficient than Beta in the production of both commodities, but in terms of the internal cost ratio (determined in this example by the labor content), Alpha enjoys a relatively greater advantage in the production of wheat. This becomes evident when we consider that Alpha must give up 3 t of wheat to free up enough resources (labor) to Table 1. Production conditions in two potential trading partners In One unit of labor produces country Alpha Beta 6 t wheat or 2 t textiles 2 t wheat or 1 t textiles Absolute production Wheat: Textiles cost per unit domestic value ratio 1/6 unit labor 3:1 1/2 unit labor 1/2 unit 'labor 2:1 1 unit labor 3 produce an additional 1 t of textiles, whereas Beta must give up only 2 t of wheat to free up enough resources (labor) to produce an additional 1 t of textiles. In other words, the resource costs (or opportunity costs) of the two commodities differ between countries: 1 t of textiles is worth 3 t of wheat in Alpha, but only 2 t of wheat in Beta. These domestic resource costs determine the limits to mutually beneficial trade. The difference in resource costs is what enables both countries to benefit from specialization and trade. Consider what will happen if the ratio of the price of wheat to the price of textiles is 2.5 to 1 in international markets. Alpha can Table 2. Net welfare gains achieved through specialization and trade Alpha Resource endowment Production cost per unit: Wheat Textiles Beta 100 units labor 100 units labor 1/6 unit labor 1/2 unit labor 1/2 unit labor 1 unit labor Without trade (assuming 50% allocaton ofresources to each product) Production and consumption 300 t wheat 100 ttextiles 100 t wheat 50 t textiles With trade (assuming 100% allocation ofresources to product with comparative advantage) Specialized production 600 t wheat 100 t textiles Quantity given up in trade 250 t wheat 50 t textiles Quantity received in trade 100 ttextiles 125 t wheat Consumption 350 t wheat 100 ttextiles 125 t wheat 50 t textiles 50 t wheat 25 t wheat Net welfare gains Note: International exchange ratio is 1 t textiles = 2.5 t wheat. 4 acquire 1 t of textiles by exporting only 2.5 t of wheat, which would be cheaper than producing the textiles domestically at an opportunity cost of 3 t of wheat. Conversely, by exporting 1 t oftextiles, Beta can obtain 2.5 t of wheat, more than the 2 t of wheat it would have been able to produce with the same resources. Thus, in this simple example, both countries can benefit by exploiting their respective comparative advantage: Alpha would be better off specializing in wheat and trading for textiles, while Beta would be better off specializing in textiles and trading for wheat. The net welfare gains from specialization and trade are apparent in Table 2 in the form of higher levels of consumption in both countries. In a more realistic example, the quantity of labor required to produce either wheat or textiles would not be constant over the entire feasible range of production. In that case, specialization in production would probably be less than complete, and each country would continue to produce some quantity of both goods. 5 3 Review of the Domestic Resource Cost Methodology Applied comparative advantage analysis essentially seeks to answer the following question: for a given country or region, which among a set of alternative production activities is relatively most efficient (measured in terms of contribution to national income), ignoring the effects of distortions in the economy resulting from government policies and market failures? Relative efficiency in production--and hence comparative advantage--depends on three factors: 1) technology (which determines production possibilities and influences rates of product transformation); 2) the resource endowment (which determines the value of domestic resources, e.g., land, labor, capital, and water); and 3) international prices (which determine the value of all other inputs and outputs). The DRC method described in this paper generates several measures of the relative economic efficiency of production alternatives. One of these measures, net social profitability (NSP), indicates the contribution of each production alternative to national income, measured in terms of social net returns to land. A second measure, the resource cost ratio (RCR), indicates the efficiency of each production alternative in using domestic resources to earn (or save) one unit of foreign exchange. Since both measures capture the ability of production alternatives to contribute to national income, comparison of social profitability and! or RCRs provides an empirical measure of the underlying pattern of comparative advantage. Step 1: Developing Enterprise Budgets DRC analysis begins with the development of an enterprise budget for each production alternative being compared. Typically these production alternatives will consist of different crops which compete for resources. However, they may also consist of the same crop grown in different locations, for example when policy makers are trying to determine which of two regions within the same country enjoys a comparative advantage in the production of a given crop. Alternatively, they may consist of the same crop grown using different levels of technology, for example when policy makers are trying to determine whether a country enjoys a comparative advantage in large-scale mechanized production ofa crop or small-scale, labor-intensive production. Since calculation of RCRs depends on accurately accounting for all inputs and outputs, the budgets must be fairly detailed. One important use of the enterprise budgets is to permit opportunity costing of primary factors of production (e.g., land, labor, and capital). Consequently, budgets must be constructed for all reasonable production alternatives in a given region. Many applied comparative advantage studies appearing in the literature focus too narrowly on one or two enterprises of immediate interest. By ignoring viable production alternatives, these studies may incorrectly estimate the opportunity costs of primary factors, especially land. 6 Step 2: Classifying Inputs and Outputs After enterprise budgets have been constructed and verified, all inputs and outputs must be classified as primary factors or tradables. This distinction is necessary because RCRs are calculated as the ratio between the total opportunity cost of primary factors and the value added to tradables. Also, shadow prices are often determined differently for primary factors and tradables. For these reasons, the two categories of goods must be differentiated. Primary factors are defined as goods that are not normally traded internationally and include chiefly land, labor, water, and capital. 1 Tradables are defined as goods that are traded internationally or potentially could be traded. The fact that some potentially tradable goods may not actually be imported or exported (because of economic or political reasons) does not affect their status as tradables; such goods are known as "non-traded tradables" and are classified as tradables. Some non-traded production inputs will turn out to be composite goods comprising both a tradable component and a primary factor component. For example, transport costs incurred in delivering fertilizer to the farmer's field include both the cost of fuel and machinery (tradables), as well as labor costs (a primary factor). Similarly, the cost of the machinery repairs and maintenance may include both the cost of spare parts (tradables), as well as labor costs (a primary factor). If such non-traded composite goods are used in production, it is necessary to decompose them into the tradable component and the primary factor component. Step 3: Determining Market Prices and Social Prices Once production alternatives have been identified, enterprise budgets developed, and inputs and outputs classified into tradables and primary factors, a vector of economic (or shadow) prices must be constructed. Referred to here as "social prices", these prices are intended to reflect the true economic value of goods and services in the absence of taxes, subsidies, import tariffs, quotas, price controls, and other government policies. Accurate estimation of social prices is critically important in DRC analysis, because these prices represent the opportunity cost to the economy of inputs and outputs. Social prices are thus extremely influential in determining comparative advantage rankings, which are based on the ability of alternative enterprises to contribute to national income. 1 Although labor might be considered tradable in cases where seasonal migration results in remittances offoreign exchange, it is usually treated as a primary factor in DRC analysis because the international labor market generally is not well developed. 7 Social prices prices are are determined determined differently differentlyfor for primary primaryfactors factors and andtradables. tradables. Social Primaryfactors factors are are assigned assignedsocial social prices prices equal equal to to their theiropportunity opportunitycost costvalue value Primary (i.e., the the returns returns in in their their most mostsocially sociallyprofitable profitable alternative alternative use). use). While While the the (i.e., opportunitycost costvalue valueof ofland landfrequently frequently can can be be estimated estimatedfrom from the the enterprise enterprise opportunity budgets themselves themselves (as (asthe the residual residual returns returns to toland landin inthe the most most socially sociallyprofitprofitbudgets able cropping croppingalternative), alternative), opportunity opportunitycost costvalues values for forthe the other otherprimary primary able factors, especially especiallylabor laborand and capital, capital, are are often oftendifficult difficultto to establish. establish. Estimating Estimating factors, social prices pricesfor for labor laborand and capital capitalinvolves involves adjusting adjustingmarket marketprices prices by bysome soIlie social compensatoryconversion conversionfactor factor selected selectedto toreflect reflect the the estimated estimateddegree degree of of compensatory distortion prevailing prevailingin inthe the economy. economy. distortion Tradables are are valued valued at at their theirworld world price priceequivalent, equivalent, i.e., i.e., the the price price at at which which Tradables theycan can be beimported importedor orexported, exported, adjusted adjusted for for transport transport costs costs and and exchange exchange they rate anomalies. anomalies. In In the the case case of ofimported importedgoods, goods, domestic domestictransportation transportationand and rate handlingcosts costs are are added added to to the the CIF CIF price price to to arrive arrive at ataa social social price priceequivalent equivalent handling tothe the import importparity parity price; price; in in the the case case of ofexported exportedgoods, goods, domestic domestic transportatransportato tion and andhandling handlingcosts costs are are subtracted subtractedfrom from the the FOB FOB price price to to arrive arrive at at aa social social tion priceequivalent equivalentto tothe theexport exportparity parity price. price. Since Since domestic domestictransportation transportation and and price handlingcosts costs may maybe be considerable, considerable,ititisisimportant importantto to select selectproduction productionand and handling consumption reference reference points points that that accurately accuratelyreflect reflectthe the geographical geographical distribudistribuconsumption tionof ofproduction production and and consumption consumption activities. activities.22 tion Because decisions decisions based basedon on the the results results of ofDRC DRC analysis analysistypically typically have have aa longer longer Because term perspective, perspective, ititmay may be be appropriate appropriate to to use use projected projectedintermediateintermediate- or orlonglongterm run CIF CIF and and FOB FOB prices pricesin incalculating calculatingimport importand and export export parity parityprices pricesfor for both both run inputs and andoutputs. outputs. Use Use of ofprojected projectedintermediateintermediate- or orlong-run long-run prices prices rather rather inputs than current current prices priceshelps helps overcome overcomethe the problem problem of ofinternational internationalmarket market price price than variability, which which isis considerable considerablefor for many many commodities. commodities. Of Ofcourse, course, reliable reliable variability, intermediate- or orlong-run long-run price price projections projectionsare are not not always always available, available, especially especially intermediateinputs. One Oneconservative conservative approach approach for for dealing dealingwith with international international price price for inputs. for Thisisisparticularly particularlyimportant importantin inthe thecase caseoflow-value oflow-valuefood foodcrops, crops,for forwhich whichthe the 22 This borderprices pricesisis usually usuallyvery veryhigh. high. This Thismeans means ratioof ofdomestic domestictransport transportcosts coststotoborder ratio thatititmay maybe beefficient efficientfor for aacountry countrytotoproduce produce aacommodity commodityin inremote remoteregions regionsfor for that consumption within these regions and to import the same commodity for consumption within these regions and to import the same commodity for consumptionin inmore more accessible accessibleborder borderzones. zones. consumption 88 variability is to start with longer term trend prices and then to conduct sensitivity analysis to determine whether or not comparative advantage rankings are robust with respect to prices of individual outputs or inputs. Table 3 presents an example of the calculation of social prices for imported fertilizers. Table 3. Establishing social prices for fertilizer at the farm level, Nakuru area, Kenya, 1987 Diammonium phosphate Long term world price, FOB US Gulf Ports (US$/t) 205 plus Freight and handling, US Gulf Ports to East Africa (US$/t) +----±Q equals CIF Mombasa (US$/t) 245 times Equilibrium exchange rate (Ksh:US$) equals CIF Mombasa (Ksh/t) Calcium ammonium nitrate + 184.5 ---..A.Q 224.5 18.15 4,075 * 18.15 4,447 plus Port charges and rail freight, Mombasa-Nakuru (Ksh/t) + 452 equals On-rail price, Nakuru (Ksh/t) 4,899 equals On-rail price, Nakuru (Ksh/50 kg bag) 245 + 452 4,527 226 plus Retailing margin, including packaging (25%) (Ksh/bag) + equals Social retail price, Nakuru (Ksh/bag) + ---.lili ~ 306 plus Transport to farm (Ksh/bag) equals On-farm social price (Ksh/bag) Actual price paid on farm (Ksh/bag) Ratio market price to social price 282 + -----2 288 234 215 0.75 0.75 Source: Longmire and Lugogo, 1989. Note: Transport costs are net of indirect taxes (e.g., subsidy to railroad, sales tax on gasoline). 9 World reference prices (CIF and FOB) may not be available for certain specialized tradables, for example, farm machinery, irrigation equipment, or agricultural chemicals. Social prices for these types of non-standard tradables are estimated by starting with the domestic market price and removing policyinduced distortions such as tariffs, taxes, and exchange rate anomalies to arrive at the equivalent of an import or export parity price. As before, the objective is to arrive at a social price that accurately reflects the economic value of the good or service in the economy. Table 4 presents an example of the calculation of social prices for non-standard tradables for which world reference prices were not available. In calculating social prices for tradables, it is often necessary to estimate a shadow exchange rate for converting between domestic currency and international currencies. Exchange rate distortions must be taken into account in DRC analysis, because they affect the domestic prices of tradables. When the domestic currency is overvalued, imported goods appear cheaper in domestic currency terms (because they can be purchased with fewer units of the overvalued domestic currency), while exported goods appear more expensive for foreign buyers (because more units of the foreign currency are required to pay for them). When the domestic currency is undervalued, the effects are opposite. Consequently, if an adjustment is not made to correct for exchange rate distortions, comparative advantage rankings will be biased in favor of import-intensive activities (in the case of overvalued domestic currency) or in favor of export-intensive activities (in the case of undervalued domestic currency).3 A full set of market price data should be collected and retained when social prices are estimated so that the effects of government policies and market failures can later be quantified and disaggregated. Since the calculation of social prices in any event often begins with market prices, the additional effort involved is usually minimal. 3 Alternate methods for calculating the shadow exchange rate are discussed in "Estimating an Equilibrium Exchange Rate," page 33. 10 ~ ~ 343,000 32,000 66,000 95,000 35,660 1,223,000 33,000 45,500 25,200 Tractor, 75 HP (Ksh) 3-disc plow (Ksh) 10-ft harrow (Ksh) 12-ft drill (Ksh) 36-ft sprayer (Ksh) 16-ft harvester (Ksh) 7oft reaper (Ksh) Large thresher (Ksh) Small thresher (Ksh) 1 2 3 4 5 137,200 19,200 39,600 38,000 14,264 489,200 19,800 27,300 10,080 6.57 39.54 116.91 4.50 23.88 2.90 2,563 820 1,025 1,025 513 4,100 410 1,025 103 0.26 1.03 1.03 1.03 1.03 0.87 0 0 0 0 0 0 0 0 0 6.78 27.37 81.53 2.84 16.41 0.51 203,238 11,980 25,375 55,975 20,884 729,700 12,790 17,175 15,018 8.29 63.86 190.24 6.63 38.29 1.52 223,561 13,178 27,913 61,573 22,972 802,670 14,069 18,893 16,519 9.12 70.25 209.26 7.30 42.12 1.67 (f=e* 1.1) (() (e=a-b-c·d) (e) Adjusted import price' (d) Domestic Estimated Estimated transport Import import cost2 duty' price (c) (h) (i) 2,563 820 1,025 1,025 513 4,100 410 1,025 103 0.26 1.03 1.03 1.03 1.03 0.87 150.749 20,997 43,406 41,732 15,656 537,847 21,719 29,876 11,081 4.02 30.55 90.12 3.57 18.49 2.54 376,873 34,995 72,344 104,329 39,141 1,344,617 36,198 49,794 27,703 13.39 101.82 300.41 11.89 61.63 5.09 (i=f+g+h) Revised Social Domestic domestic price transport value at cost added" farm level (g) Domestic value added =fixed percentage ofmarket price (varies by item). Domestic transport cost = weight* domestic freight rate. Estimated import duty = fIxed percentage of import price (varies by item). Adjusted import price =estimated import price * 1.1 (reflects estimated 10% overvaluation ofthe Kenyan shilling). Revised domestic value added =fIxed percentage of adjusted market price (varies by item). Source: Longmire and Lugogo. 1989. 21.90 131.80 389.70 15.00 79.60 5.80 Domestic value added' Gunnies (Ksh) Buctril (KshIL) Roundup (KshIL) Dipterex 5% (Ksh/kg) Malathion (Ksh/kg) Diesel (KshIL) (b) (a) Average market price at farm level Table 4. Establishing social prices for non-standard tradable inputs at the farm level, Nakuru area, Kenya, 1987 0.91 0.91 0.91 0.91 0.91 0.91 0.91 0.91 0.91 1.64 1.29 1.30 1.26 1.29 1.14 (j=a/i) W Ratio of market price to social price Step 4: Calculating Net Social Profitability Once social prices have been estimated, the net social profitability (NSP) of each production alternative can be calculated. This is a straightforward procedure involving use of the enterprise budgets and social prices to calculate net social returns (usually to land) of each competing enterprise. Table 5 presents a sample set ofenterprise budgets showing the calculation ofnet social profitability. Assuming social prices have been estimated accurately, social profitability rankings provide a preliminary indication of comparative advantage. Social prices reflect the true economic scarcity value of inputs and outputs, so the enterprise with the largest positive NSP represents the most profitable production alternative in terms of contributing to national income. Furthermore, because social prices for primary factors are set equal to their alternative use values, the NSP figures automatically indicate relative efficiency in production and thus provide an empirical measure of comparative advantage. Some of the CIMMYT case studies have used social profitability rankings as the sole indicator of comparative advantage. However, one shortcoming of the NSP measure is that it provides no explicit information about the use of tradables (and hence foreign exchange) in production. Therefore, it is often helpful additionally to calculate RCRs for each enterprise.The RCRs are simply a restatement of NSPs, expressed not in terms of domestic currency, but rather as a unitless ratio (value of primary factors: value-added to tradables). The big advantage of RCRs is that they provide an explicit indication of the efficiency with which each production alternative uses domestic resources to generate or save foreign exchange, which makes them easy to interpret. Also, because they are not denominated in units of domestic currency, RCRs lend themselves more readily to cross-country comparison (although care should be exercised in comparing RCRs between countries, since they reflect productive efficiency relative to very different patterns of resource endowments). 12 Table 5. Enterprise budgets for irrigated crops in Zimbabwe, 1986 (Z$lha) Wheat Maize Soybeans Ground· nuts Gross social returns 1,979.45 1,686.00 1,020.00 1,627.50 Fixed costs Irrigation costs Dam and pump Irrigation equipment 74.81 74.81 24.94 24.94 24.94 24.94 54.86 54.86 64.84 64.84 39.48 39.48 Farm machinery costs Tractor depreciation Tillage equipment depreciation Cost of capital 56.73 5.84 47.29 82.39 8.48 68.67 43.03 4.43 35.87 64.76 6.66 53.97 53.00 5.45 44.18 102.22 10.52 85.20 Cotton 2,923.38 12,428.19 Tobacco barns and sheds Variable costs Machinery operation costs Tractor fuel Tractor oils Tractor repair and maintenance Tillage equipment repair and maintenance Purchased inputs Seed (and treatment) Fertilizer and lime Herbicides Pesticides Fungicides Packing materials Irrigation costs Electricity Repairs and maintenance Tobacco 163.00 39.73 2.96 53.51 57.70 4.30 77.72 30.14 2.25 40.59 45.35 3.38 61.08 37.12 2.77 49.99 0.71 1.04 0.54 0.81 0.67 72.00 308.38 13.18 4.93 35.75 222.00 45.76 12.96 71.75 115.07 70.80 9.82 15.72 169.89 56.46 163.81 5.00 266.17 525.80 10.89 8.93 2.50 111.25 126.08 108.66 21.77 180.59 8.59 7.75 38.00 244.80 16.03 81.60 5.34 179.52 5.34 212.16 11.76 129.20 13.89 8.46 135.90 55.00 81.90 51.29 390.10 Contract hire services Aerial pesticide application Aerial fertilizer application Combine harvesting Transport, farm to depot 74.64 60.78 Other costs Fertilizer transport/handling Crop insurance Drying Levy 27.24 6.93 2.98 9.90 Labor costs Skilled labor Unskilled labor Interest on working capital (6 mo.) 112.75 161.11 13.65 100.91 22.00 6.51 16.76 11.69 11.80 12.57 4.08 2.95 15.30 24.41 40.93 364.00 239.50 167.00 6.59 39.18 9.57 89.16 5.00 26.73 7.52 137.87 6.16 219.14 11.88 618.50 89.58 72.69 55.09 102.52 109.09 278.32 Total fixed costs Total variable costs 259.48 1,084.94 209.41 866.75 133.21 667.24 235.12 1,060.99 232.31 1,185.30 439.91 3,370.79 Total costs 1,344.42 1,076.17 800.45 1,296.11 1,417.61 3,810.69 635.03 609.83 219.55 331.39 1,505.77 8,617.50 Net social returns (social profitability) 19.91 9.61 74.76 40.37 Source: Morris, 1988a. 13 Step 5: Calculating Resource Cost Ratios Using data from the enterprise budgets, RCRs can be calculated according to the following formula: RCRc = (L Wpp F ) / ( P CC T - L P.T. ) 11 where: RCRc WP F pP c Tc P T. I I = = = = = = = resource cost ratio for crop c social prices (opportunity costs) of primary factors primary factors of production (usually per ha) social prices (world price equivalents) of crop c quantity produced of crop c (usually per ha) social prices (world price equivalents) of tradable inputs quantity used of tradable production inputs (usually per ha) If the enterprises being compared all compete directly for land and other resources, only one enterprise will show a positive RCR between 0 and 1. This is because the net social returns to land used in the most profitable enterprise represents the opportunity cost (or social price) ofland used in all other enterprises, which by definition drives the RCRs of these other enterprises above 1. Only if additional assumptions are introduced limiting direct competition between enterprises is it possible to end up with multiple RCRs between 0 and 1 (e.g., if two crops are grown on the same land but in different seasons). Calculation of RCRs becomes more complicated if one or more enterprises generates joint products (e.g., groundnut oil and cake; milk, meat, and leather). In such cases, the different social prices for each final joint product must be converted into social price equivalents per unit of the initial production output (e.g., ton of groundnuts; ton oflive cattle). The social price equivalents ofthe joint products can then be added to obtain the value of production per unit land area (or net social profitability of the enterprise). In this procedure, domestic processing costs should also be adjusted, if they are distorted by government policies or market failures. Table 6 presents an example of the calculation of RCRs. Following the alternative use value approach, in this example the social price of land for each enterprise has been set equal to net social profitability (NSP) of land in the most profitable alternative use (as revealed by enterprise budgets calculated previously). Since the most profitable alternative use varies between enterprises, the social price ofland is not always the same. Interpretation of RCRs is summarized in Table 7. A positive RCR between 0 and 1 indicates that the value of the domestic resources used in production is less than the value of the foreign exchange earned or saved; thus, a country has a comparative advantage in products associated with such a RCR, since the country earns or saves foreign exchange in their production. A positive RCR 14 Table 6. Resource cost ratios for irrigated crops in Zimbabwe, 1986 Wheat (Z$/ha) Maize (Z$lha) Soybeans (Z$lha) Groundnuts (Z$lha) Cotton (Z$lha) Tobacco (Z$lha) 1,979.45 1,886.00 1,020.00 1,627.50 2,923.38 12,428.18 Inputs Machinery depreciation 212.19 0.75 Repairs and maintenance 52.69 Fuels and oils 42.69 Purchased inputs 394.48 44.01 0.5* Transport 0.5 *Machinery hire charges 37.32 Packing materials 10.89 244.80 Electricity 140.75 63.08 62.00 316.47 60.41 6.83 8.93 81.60 97.34 34.86 32.38 267.43 26.47 37.38 2.50 81.60 181.14 55.24 48.73 548.85 51.95 0.00 8.59 179.52 188.13 48.42 39.88 405.88 34.03 67.95 7.75 212.16 191.71 127.18 112.75 796.97 195.05 27.50 38.00 129.20 Tradables Outputs Value of production Miscellaneous Drying Insurance Levies 2.98 6.93 9.90 9.61 11.80 2.95 3.50 13.12 7.73 28.99 11.69 40.93 239.50 364.00 167.00 Primary factors Capital 89.58 72.69 55.09 102.52 109.09 278.32 Labor 0.25*Repairs and maintenance 0.5* Transport 0.5 * Machinery hire charges 45.77 17.56 44.01 37.32 98.73 21.03 60.41 6.83 31.73 11.62 26.45 37.38 145.39 18.41 51.95 0.00 225.30 16.14 34.03 67.95 630.33 42.39 195.05 27.50 0.00 1,549.94 1,549.94 1,549.94 678.50 5,137.21 234.24 847.38 1,809.63 852.93 1,712.21 347.04 1,868.21 460.48 1,131.01 1,826.18 6,310.80 10,716.83 0.28 2.12 4.93 4.06 0.62 0.59 Landa Net cost-primary factors Value added-tradables Resource cost ratios Source: Morris, 1988a. a Residual returns to land in best competing alternative valued at world price equivalent. Alternatives assumed as follows: wheat vs. fallow; tobacco vs. rainfed tobacco; maize vs. soybeans vs. cotton VB. groundnuts. Residual returns (Z$lha) =wheat, 682.31; maize 678.50; soybeans, 255.42; groundnuts, 385,36; cotton, 1,549.94; tobacco, 8,702.70; and rainfed tobacco, 5,137.21. 15 above above1 indicates 1 indicates that that the thevalue value ofof the thedomestic domesticresources resourcesused used ininproduction production exceeds exceeds the thevalue value ofof the theforeign foreignexchange exchange earned earned ororsaved, saved,and and the thecountry country does doesnot not have havea acomparative comparative advantage advantage ininproduction. production.A Anegative negativeRCR RCR indiindicates catesthat that foreign foreignexchange exchange is is being being wasted, wasted, i.e., i.e.,more more foreign foreignexchange exchange is isused used inin production production ofof a commodity a commodity than than the thecommodity commodity is isworth. worth. Step Step6:6:Conducting ConductingSensitivity SensitivityAnalysis Analysis One Oneconvenient convenient feature featureofof the theDRC DRC framework framework is isthat that it it lends lendsitself itself readily readily toto sensitivity sensitivity analysis. analysis.With Withthe thehelp helpofof any any standard standard computer computer spreadsheet spreadsheet package, package, it it is iseasy easy totodetermine determinewhether whether comparative comparativeadvantage advantage rankings rankingsare are Table Table7. 7.Interpretation Interpretationofof resource resourcecost costratios ratios(RCRs) (RCRs) Value ValueofRCR ofRCR Interpretation Interpretation oo<RCR< <RCR<1 1 Value Valueofof domestic domesticresources resources used used ininproduction production is is less lessthan than value valueofof foreign foreignexchange exchange earned earned oror saved saved == comparative comparative advantage. advantage. RCR> RCR>1 1 Value Value ofof domestic domesticresources resourcesused usedininproduction production is is greater greater than than value valueofof foreign foreignexchange exchangeearned/saved earned/saved ==nonocomparative comparativeadvantage. advantage. RCR<O RCR<O More More foreign foreignexchange exchangeused used ininthe theproduction production ofof aa than thanthe thecommodity commodity is isworth worth commodity commodity == nonocomparative comparativeadvantage. advantage. sensitive sensitive totochanges changes inin individual individualparameters. parameters.Sensitivity Sensitivity analysis analysisis is imporimportant, tant,because because technical technicalcoefficients coefficients used used ininconstructing constructing enterprise enterprise budgets budgets (e.g., (e.g., yields, yields,use useofof inputs) inputs)are areoften often mean mean values valuescalculated calculated from froma arange rangeofof observed observed values, values,and and because becauseprices prices used used inin calculating calculating social socialprofitability profitability the theshadow shadow foreign foreignexchange exchange rate) rate)are areoften oftenestimated estimated prices pricesoror (including (including projected projected prices. prices.Sensitivity Sensitivity analysis analysiscan can reveal reveal whether whether comparative comparative advanadvantage tagerankings rankingscalculated calculated using using mean mean values, values,estimated estimated values, values,ororprojected projected values valuesforfortechnical technical coefficients coefficients and andsocial socialprices pricesare arelikely likely totochange change iftechniiftechnicalcal coefficients coefficientsand/or and/or social socialprices prices eventually eventually differ differfrom fromexpectations. expectations. 1616 Which parameters should be tested through sensitivity analysis? While the robustness of DRC results will tend to vary depending on enterprise substitution possibilities, technology, and relative prices, social profitability levels and RCRs frequently are sensitive to the following parameters. World reference prices of outputs Comparative advantage rankings tend to be highly sensitive to world reference prices of outputs. Ceteris paribus, a change in the world reference price of an output will have a greater effect on the social profitability (and the RCR) of an enterprise than a change of similar magnitude in any other parameter. Since social prices of outputs are based on long-term trends in world reference prices, which may not provide an accurate projection of future prices, it is generally a good idea to determine whether comparative advantage rankings are sensitive to changes in world reference prices of outputs. Yields Comparative advantage rankings tend also to be highly sensitive to the level of yields assumed for any fixed quantity of inputs. To the extent that improved management can succeed in raising mean yields above current levels, enterprises that appear socially unprofitable at present could become socially profitable in the future. Table 8 presents data from Zimbabwe showing the expected social profitability of rainfed wheat under four yield levels, assuming no change in inputs use and no changes in prices.' Table 8. Social profitability of rainfed wheat in Zimbabwe under four ;yield levels, 1986 Rainfed wheat at yield of: 1.5 t/ha 2.0 t/ha 2.5 t/ha 3.0 t/ha Estimated social net returns to land: (Z$/ha) (47) 125 297 469 Source:~orris, 1988b. 17 Exchange Exchangerate rate InIncases caseswhere wherea ashadow shadowexchange exchangerate ratehas hasbeen beenestimated estimatedtotocorrect correctforfor apparent apparentdistortions distortionsininthe theofficial officialexchange exchangerate, rate,ititisisgenerally generallya agood goodidea ideatoto conduct theexchange exchangerate. rate.Because Becauseshadow shadowexchange exchange conductsensitivity sensitivityanalysis analysisononthe rates ratesare arenotoriously notoriouslydifficult difficulttotoestimate estimateempirically, empirically,conducting conductingsensitivity sensitivity analysis guardagainst againstestimation estimationerrors. errors.Whether Whetherorornot notcomcomanalysisisisone oneway waytotoguard parative parativeadvantage advantagerankings rankingsturn turnout outtotobebesensitive sensitivetotothe theexchange exchangerate ratewill will the depend theforeign-exchange foreign-exchangeintensity intensityofof theenterprises enterprisesbeing being dependlargely largelyononthe compared. the tradable output compared.IfIf theuse useofof tradableinputs inputsper perunit unitvalue valueofof outputisisrelatively relatively similar similaracross acrossallallenterprises, enterprises,changes changesininthe theshadow shadowexchange exchangerate ratewill willaffect affect social socialprofitability profitabilitylevels levelsmore moreororless lessequally, equally,and andcomparative comparativeadvantage advantage rankings the rankingsare arelikely likelytotoremain remainunaffected. unaffected.On Onthe theother otherhand, hand,ifif theuse useofof tradable tradableinputs inputsvaries variessignificantly significantlybetween betweenenterprises, enterprises,changes changesininthe theshadow shadow exchange ratewill willhave havedifferent differenteffects effectsononsocial socialprofitability profitabilitylevels, levels,and and exchangerate comparative comparativeadvantage advantagerankings rankingsare arelikely likelytotochange. change.The Theexchange exchangerate ratemay may also alsobebeimportant importantwhen whenthe theproduction productionalternatives alternativesinclude includenon-traded non-tradedcrops crops (whose (whosesocial socialprice priceisisestablished establishedininthe thedomestic domesticmarket) market)vs.vs.imported importedoror exported aredetermined determinedininthe theworld worldmarket). market). exportedcrops crops(whose (whosesocial socialprices pricesare Wage Wagerate rate InIncases caseswhere wherea ashadow shadowwage wagerate ratehas hasbeen beenestimated estimatedtotocorrect correctforforapparent apparent distortions distortionsininthe thelabor labormarket, market,ititmay maybebeuseful usefultotoconduct conductsensitivity sensitivityanalysis analysis the ononthe thewage wagerate. rate.AsAsininthe thecase caseofof theshadow shadowexchange exchangerate, rate,not notthe theleast least reason reasonforforthis thisisisthat thatshadow shadowwage wagerates ratesare arenotoriously notoriouslydifficult difficulttotoestimate estimate empirically; empirically;thus, thus,conducting conductingsensitivity sensitivityanalysis analysisononthe theshadow shadowwage wagerate rateisis one waytotoguard guardagainst againstestimation estimationerrors. errors.Whether Whetherorornot notcomparative comparative oneway advantage advantagerankings rankingsturn turnout outtotobebesensitive sensitivetotothe theshadow shadowwage wagerate ratewill will depend the the dependlargely largelyononthe thelabor laborintensity intensityofof theenterprises enterprisesbeing beingcompared. compared.IfIf the use labor output useofof laborper perunit unitvalue valueofof outputisisrelatively relativelysimilar similaracross acrossallallenterprises, enterprises, changes theshadow shadowwage wagerate ratewill willaffect affectsocial socialprofitability profitabilitylevels levelsmore moreoror changesininthe less lessequally, equally,and andcomparative comparativeadvantage advantagerankings rankingsare arelikely likelytotoremain remainunafunafthe labor fected. theother otherhand, hand,ifif theuse useofof laborvaries variessignificantly significantlybetween between fected.On Onthe enterprises enterprises(e.g., (e.g.,mechanized mechanizedvs.vs.manual manualproduction productiontechnologies), technologies),changes changesinin the theshadow shadowwage wagerate ratewill willhave havedifferent differenteffects effectsononsocial socialprofitability profitabilitylevels, levels, and andcomparative comparativeadvantage advantagerankings rankingsare arelikely likelytotochange. change. 1818 44 Uses Usesof ofDomestic Domestic Resource ResourceCost CostAnalysis Analysis The Thefollowing followingexamples examplesdrawn drawnfrom fromCIMMYT CIMMYTcase casestudies studiesdemonstrate demonstratehow how the theDRC DRCframework frameworkcan canbebeadapted adaptedtotoaddress addressa awide widerange rangeofofcomparative comparative advantage advantageissues. issues. Revealing RevealingDistorting DistortingEffects EffectsofofGovernment GovernmentPolicies Policies Before BeforeRCRs RCRsare areformally formallycalculated calculatedand andanalyzed, analyzed,private privateand andsocial socialprofitabilprofitability itycan canbebecompared comparedfor foreach eachenterprise enterprisetotodetermine determineififand andhow howgovernment government policies policiesinfluence influenceproduction productionincentives. incentives.The Theprivate privateprofitability profitabilityofofananenterenterprise priseisissimply simplythe thenet netreturns returnstotoland landcalculated calculatedusing usingmarket marketprices; prices;the the social socialprofitability profitabilityisisthe thenet netreturns returnscalculated calculatedusing usingsocial socialprices. prices.Although Although technically technicallynot notpart partofofDRC DRCanalysis analysisitself, itself,this thiscomparison comparisoncan canbebeperformed performedatat little littleadditional additionalcost, cost,since sincethe theprocess processofofcalculating calculatingRCRs RCRsgenerates generatesallallthe the required requireddata. data. The Thepurpose purposeofofcomparing comparingprivate privateand andsocial socialprofitability profitabilityshould shouldbebeobvious. obvious. Whenever Wheneverdiscrepancies discrepanciesexist existbetween betweenmarket marketand andsocial socialprices, prices,the theinterests interestsofof farmers farmersand andofofthe thenation nationcan candiverge. diverge.AAcrop cropcan canbebeprofitable profitabletotofarmers farmers(e.g., (e.g., because becauseofofoutput outputororinput inputprice pricesubsidies), subsidies),even eventhough thoughitsitsproduction productionmay maynot not represent representananefficient efficientuse useofofresources resourcesfrom fromthe thepoint pointofofview viewofofthe thecountry. country. Conversely, Conversely,a acrop cropcan canbebeunprofitable unprofitabletotofarmers farmers(e.g., (e.g.,because becauseofofoutput outputoror input inputprice pricetaxation), taxation),even eventhough thoughitsitsproduction productionrepresents representsananefficient efficientuse useofof the thenation's nation'sresources. resources.By Bycomparing comparingprivate privateprofitability profitabilitywith withsocial socialprofitabilprofitabilnotonly onlycan canthe theoverall overalleffect effectofofgovernment governmentpolicies policiesbebemeasured, measured,but butthe the ity, ity,not influence influenceofofindividual individualpolicies policiescan canbebequantified quantifiedbybydisaggregating disaggregatingthe theoverall overall discrepancy discrepancyinto intoitsitsconstituent constituentparts. parts. Policy Policyeffects effectsononproducer producerincentives incentivesappear appearasasthe thedifference differencebetween betweenthe theprice price ofofa aparticular particularproduct productororinput inputvalued valuedatatmarket marketprices pricesand andatatsocial socialprices. prices. These Thesepolicy policyeffects effectsare aresummarized summarizedininTable Table9.9.Thus, Thus,the theeffect effectofofa atariff tariffonon imports importsofofa acommodity commodityisisindicated indicatedbybyK,K,the theeffect effectofofa asubsidy subsidyononfertilizer fertilizerisis indicated indicatedbybyL,L,the theeffect effectofofa alabor labormarket marketdistortion distortionisisindicated indicatedbybyM,M,and andthe the indirect indirecteffects effectsofofpolicies policiesononcompeting competingenterprises enterprisesthat thatlead leadtotodistortions distortionsinin the themarket marketvalue valueofofland landare areindicated indicatedbybyNN(assuming (assumingthat thatthese theseeffects effectsare are reflected reflectedresidually residuallyininnet netreturns returnstotoland). land).Total Totalnet netpolicy policyeffects effectsare areindicated indicated bybythe thedifference differencebetween betweenprivate privateand andsocial socialnet netprofitability profitability(NPP-NSP), (NPP-NSP),with with a apositive positivevalue valueindicating indicatingthat thatgovernment governmentpolicies policiesononthe thewhole wholeincrease increase private privateprofitability, profitability,and anda anegative negativevalue valueindicating indicatingthat thatgovernment governmentpolicies policies ononthe thewhole wholedecrease decreaseprivate privateprofitability. profitability.Table Table9 9also alsoshows showshow howthe thesame same information informationused usedininDRC DRCanalysis analysiscan canalso alsobebeused usedtotocalculate calculatemore moreconvenconventional tionalmeasures measuresofofpolicy policyincentives, incentives,such suchasasnominal nominalprotection protectioncoefficients coefficients andeffective effectivesubsidy subsidycoefficients coefficients (NPC), (NPC),effective effectiveprotection protectioncoefficients coefficients(EPC), (EPC),and (ESC). (ESC). .. 1919 Table 9. Measures of comparative advantage and policy incentives Tradables Products Inputs Market prices World price equivalent Opportunity cost of resources Policy effect Non·tradables Capital and labor Land Profit D NPP=A·B·C·D A F B G C K=A-F L=G·B M=H·C H Measures of comparative advantage Resource cost ratio (RCR) Measures of policy incentives Nominal protection coefficient (NPC) Effective protection coefficient (EPC) Effective subsidy coefficient (ESC) NSP=F·G·H·I I N=I-D O=NPP·NSP =K+L+M+N (H+I)/(F·G) = AlF (A·B)/(F·G) OfF Source: Adapted from Monke and Pearson, 1989. A good example of the insights which can be obtained by comparing private and social profitability measures appears in Morris' (1988) study of wheat in Zimbabwe. Although this study was undertaken primarily to determine whether or not Zimbabwe has a comparative advantage in wheat production, the DRC framework of analysis at the same time provided an opportunity to evaluate the claim made by commercial farmers that government policies strongly discriminate against the farming sector. Table 10 presents data from the Zimbabwe study showing the effects of government policies on production incentives for six major commercial crops--wheat, tobacco, cotton, maize, soybeans, and groundnuts. The difference between the private and social profitability of each crop, appearing in column 3, represents the net effect of government policies on producer incentives. This overall policy effect is disaggregated into effects attributable to specific taxes and subsidies on producer prices, farm machinery prices, purchased inputs prices, labor policy, agricultural credit, and other policies. The data show how government policies affect private profitability, rarely positively (e.g., through subsidies to agricultural credit programs), and mostly negatively (e.g., through controlled producer prices, taxes on inputs, and wage policies). The data furthermore reveal which crops are most affected (tobacco and cotton), and they indicate which specific policies most influence producer incentives for each crop (producer price policy and labor policy, in most cases): 20 ...... ...... I\) I\) Crop 108.22 108.22 107.82 107.82 115.77 115.77 706.93 706.93 2,698.17 2,698.17 Maize Maize Soybeans Soybeans Groundnuts Groundnuts Cotton Cotton Tobacco Tobacco a a 8,617.50 8,617.50 1,505.77 1,505.77 331.39 331.39 219.55 219.55 609.83 609.83 635.03 635.03 Social Social profit· profit· ability ability (Z$lha) (Z$lha) 0.00 0.00 0.00 0.00 (485.88) (485.88) (4,928.19) (4,928.19) (111.73) (111.73) (215.62) (215.62) (798.83) (798.83) (5,919.33) (5,919.33) (336.00) (336.00) (329.45) (329.45) (503.97) (503.97) (501.61) (501.61) Producer Producer price price policy policy (Z$lha) (Z$lha) Net Net policy policy effect effect (Z$lha) (Z$lha) Includes of energy, energy, transport, Includes effects effects of transport, and and insurance insurance policies. policies. Source: Morris 1988a. 1988a. Source: Morris 131.05 131.05 Wheat Wheat Crop - Private Private profit· profit· ability ability (Z$lha) (Z$lha) (67.01) (67.01) (76.94) (76.94) (39.41) (39.41) (55.96) (55.96) (52.55) (52.55) (54.81) (54.81) (91.86) (91.86) Purchased Purchased input input prices prices (Z$lha) (Z$lha) (29.86) (29.86) (25.93) (25.93) (28.14) (28.14) (22.14) (22.14) (41.79) (41.79) Farm Farm machinery machinery prices prices (Z$lha) (Z$lha) (618.50) (618.50) (218.84) (218.84) (137.87) (137.87) 86.51 86.51 29.33 29.33 24.90 24.90 15.22 15.22 20.10 20.10 (89.16) (89.16) (26.72) (26.72) 24.48 24.48 Credit Credit policy policy (Z$lha) (Z$lha) (39.19) (39.19) Labor Labor policy policy (Z$lha) (Z$lha) Difference Difference due due to: to: (342.80) (342.80) (26.57) (26.57) (20.76) (20.76) (19.54) (19.54) (19.60) (19.60) (26.16) (26.16) Other Other policies policies and and market market 8 distortions distortionsB (Z$lha) (Z$lha) Table of difference profitability of Table 10. 10. Sources Sources of difference between between private private and and social social profitability of irrigated irrigated crops crops in in Zimbabwe, Zimbabwe, 1987 1987 Comparison of private and social profitability thus reveals that agricultural policies in Zimbabwe provide disincentives for commercial farmers, since private profitability is less than social profitability for all major commercial crops. In other words, government policies are taxing away a portion of the social profits. However, this tax occurs across all commodities with similar incidence, so the relative ranking among crops in terms of private profitability is not greatly altered from the ranking in terms of social profitability. This information on the size and incidence of policy effects can help the government adjust specific policies to bring about desired changes in the commercial farming sector. Revealing Comparative Advantage Between Enterprises Once private and social profitability have been compared, attention turns to indicators of comparative advantage (NSP and RCRs). Probably the most common use ofDRC analysis is to determine comparative advantage between alternative enterprises, whether cropping activities or other types of agricultural production activities. A good example of this use of DRC analysis appears in Byerlee's (1985) study of wheat in Ecuador. This study was motivated by the Ecuadoran government's concern over the sharp decline in wheat production which occurred during the late 1970s and early 1980s, at a time when wheat consumption was increasing rapidly. Policy makers were interested in determining whether or not wheat production represented an efficient use of the nation's resources. Table 11 presents data from the Byerlee study showing Ecuador's pattern of comparative advantage. Wheat in Ecuador competes with three alternative enterprises: barley, potatoes, and dairying. The RCRs appearing in Table 11 (calculated using 1983 data) reveal that potato production represents the most efficient use of Ecuador's domestic resources, followed by wheat production, dairying, and finally barley production. 4 This was an important finding at the time the study was carried out, since the ranking of farmer profitabilities diverged sharply from this efficiency ranking. In the Ecuador study, government policies (including a vastly overvalued exchange rate and differential import tariffs across commodities) were found to discriminate strongly against wheat, which was the least profitable of all crops from the farmers' point of view. The strong effects of the exchange rate and of the import tariffs were particularly noteworthy, since they suggested that the most realistic way for Ecuador to increase self-sufficiency in wheat was through macro-economic policy reform, rather than through technological change within the agricultural sector. 4 22 Note that returns to potato production were not adjusted to reflect capital constraints and limited marketing opportunities. See page 34 for a discussion of the problem of predicting general equilibrium effects. Table 11. Resource cost ratios for competing enterprises in Ecuador, 1983 Inttnii.ve dairying Wheat Tradables Outputs Value of production 45,750 35,595 130,130 39,587 5,232 1,379 5,064 1,711 2,379 679 5,232 1,379 4,392 1,556 2,057 634 4,155 1,421 19,280 20,741 8,470 3,234 2,770 948 2,180 3,682 3,951 515 Primary Factors Capital - machinery Capital - working Capital - other investment 1,823 660 1,823 594 1,309 3,990 0 873 0 7,000 Labor Fertilizer distribution Machinery distribution Other inputs distribution 1,547 1,030 425 495 1,547 888 425 450 20,430 3,985 289 6,000 2,190 452 193 1,065 Landa 45,295 45,295 18,850 45,295 Net cost--primary factors Value added--tradables 51,275 29,306 51,022 20,345 54,853 72,829 56,003 25,541 1.75 2.51 0.75 2.19 Inputs Machinery depreciation Fuels and oils Fertilizer Other tradable inputs Seed Other miscellaneous costs Resource cost ratio ° ° Source: Byerlee, 1985. a Residual returns to land in best competing alternative valued at world price equivalent. Cost and returns for dairying adjusted to reflect six-month cropping cycle. 23 Revealing Comparative Advantage Between Regions Domestic resource cost analysis can also be used to determine comparative advantage rankings between different regions within the same country in producing the same crop. Even if the production technology is similar, regional differences in RCRs can arise because of differences in local cropping patterns (which affect the alternate use value of primary factors), or because of differences in transportation and handling costs between the two regions (which affect the social prices oftradables). The study carried out by Byerlee and Longmire (1986) focusing on wheat in Mexico illustrates this particular use of DRC analysis. Wheat is produced in two widely separated regions of Mexico: the northern irrigated Yaqui Valley (located far from major consumption points), and the central rainfed high plateau or altiplano (located adjacent to major consumption points). A DRC study was undertaken to shed light on the influence of government policies on producer incentives and to determine Mexico's pattern of comparative advantage in wheat production. 5 Table 12 presents data from the Byerlee and Longmire study relating to the efficiency of wheat production in two different areas of Mexico. The RCR for wheat in Sonora (Yaqui Valley) is close to 1, indicating that the value of domestic resources invested in wheat production is approximately equal to the net value-added to tradables. In contrast, the RCR for wheat in Tlaxcala (altiplano) is well below 1, indicating that the value of domestic resources invested in wheat production is less than the net value-added to tradables. These RCRs suggest that wheat production in the altiplano region is slightly more efficient than wheat production in the Yaqui Valley. This finding came as a surprise, since the relative efficiency of wheat production in the altiplano is not widely recognized. While differences in production technologies in part account for the different RCRs, differential transportation costs involved in getting wheat to the major consumption point (Mexico City) also significantly affect the comparative advantage rankings. These results would appear to justify increased investment in research to develop improved rainfed production technologies for the altiplano. In addition, they would appear to justify a government initiative to revitalize wheat production in an area where production had been declining. 5 24 In addition to the regional effect, differences in production technology also influenced the comparative advantage rankings, but these are not discussed here. Table 12. Resource cost ratios for two wheat-producing regions in Mexico, 1985 Sonora (Yaqui Valley) Tlaxcala (altiplano) Tradables Outputs Value of production Inputs Machinery depreciation Fuels and oils (net) Spare parts Purchased inputs Other miscellaneous costs 221,990 69,040 8,330 8,540 6,660 50,720 9,210 7,020 3,860 5,570 12,950 9,700 30,590 9,580 2,220 17,160 81,060 20,760 2,060 1,860 0 1,070 140,610 138,530 25,750 29,940 1.02 0.86 Primary Factors Capital (interest) Labor Maintenance Water Land Net cost--primary factors Value added--tradables Resource cost ratios Source: Byerlee and Longmire, 1985. Revealing Comparative Advantage Between Technologies Domestic resource cost analysis can also be used to determine comparative advantage between alternative production technologies used for a single crop. Even though in this case the crop remains the same, social profitability measures and RCRs may differ considerably between production technologies if the technologies require different types and quantities of inputs. Whenever production takes place across a range of farm sizes and types, it is important to consider alternative technologies; otherwise, critical issues relating to farm size and choice of technology are hidden. This is because the primary unit of analysis in DRC analysis is a single cultivated heGtare, which means that unless farm size and technology level are explicitly taken into account, social profitability measures will be identical for a crop produced on a 1-ha farm and on a 100-ha farm. 25 Longmire's and Lugogo's (1989) study wheat Kenya provides a good Longmire's and Lugogo's (1989) study ofof wheat inin Kenya provides a good this use of DRC analysis. Wheat produced Kenya large-scale example ofof this use ofDRC analysis. Wheat is is produced in in Kenya onon large-scale example commercial farms using high levels purchased inputs and machinery. The commercial farms using high levels ofof purchased inputs and machinery. The Kenyan government interested expanding wheat production into the Kenyan government is is interested inin expanding wheat production into the smallholder sector, which would necessitate a shift less capital-intensive smallholder sector, which would necessitate a shift to to less capital-intensive production technologies characterized greater use animal power and/or production technologies characterized byby greater use ofof animal power and/or human labor. Domestic resource cost analysis was undertaken attempt human labor. Domestic resource cost analysis was undertaken inin anan attempt to to assess the relative efficiency these proposed smallholder production technoloassess the relative efficiency ofof these proposed smallholder production technologies under a range farm sizes. Since wheat currently grown Kenya gies under a range ofof farm sizes. Since nono wheat is is currently grown inin Kenya using labor-intensive technologies, prototypical enterprise budgets the using labor-intensive technologies, prototypical enterprise budgets forfor the various small-scale technologies were estimated based technical inputvarious small-scale technologies were estimated based onon technical inputoutput parameters from several Asian countries where wheat produced output parameters from several Asian countries where wheat is is produced byby smallholders. smallholders. Table presents data from the Longmire and Lugogo study relating the Table 1313 presents data from the Longmire and Lugogo study relating to to the relative social profitability alternative wheat production technologies under relative social profitability ofof alternative wheat production technologies under a range field sizes. The NSP figures indicate that, the smallest sized a range ofof field sizes. The NSP figures indicate that, forfor the smallest sized fields (0.5 and 1 ha), labor-intensive production technology represents the fields (0.5 haha and 1 ha), labor-intensive production technology represents the most socially profitable use domestic resources, whereas the larger sized most socially profitable use ofof domestic resources, whereas onon the larger sized represents the most fields (>4 ha), fully mechanized production technology represents the most fields (>4 ha), fully mechanized production technology socially profitable use resources. Interestingly, none the intermediatesocially profitable use ofof resources. Interestingly, none ofof the intermediatescale mechanized production technologies represent a socially profitable use scale mechanized production technologies represent a socially profitable use ofof resources fields any size. resources onon fields ofof any size. These results suggest that labor-intensive production technologies would These results suggest that labor-intensive production technologies would bebe socially profitable Kenya smallholder wheat producers with restricted socially profitable inin Kenya forfor smallholder wheat producers with restricted access land. However, the absence constraints farm size, wheat access to to land. However, inin the absence ofof constraints onon farm size, wheat production would remain most efficient larger landholdings where high production would remain most efficient onon larger landholdings where high Table Social profitability wheat production technologies size Table 13.13. Social profitability ofof wheat production technologies byby size field, Kenya, 1987 ofof field, Kenya, 1987 Average field size Average field size Wheat technology Wheat technology 0.50.5 haha 1 ha 1 ha 4ha 4ha 10ha 10ha 40ha 40ha (Ksh/ha)(Ksh/ha) (Ksh/ha)(Ksh/ha) (Ksh/ha)(Ksh/ha) (Ksh/ha) (Ksh/ha) (Ksh/ha) (Ksh/ha) plow and labor intensive OxOx plow and labor intensive Small motorized Small motorized South Asian SouthAsian a a Large reaper and large thresher Large reaper and large thresher Fully mechanized Fully mechanized 355 355 (355) (355) (63) (63) (739) (739) (473) (473) Source: Longmire and Lugogo, 1989. Source: Longmire and Lugogo, 1989. a Tractor land preparation, mechanized threshing. a Tractor land preparation, mechanized threshing. 2626 3939 (568) (568) (622) (622) (678) (678) (39) (39) (544) (683) (544) (683) (1,059) (1,175) (1,175) (1,059) (924) (854) (924) (854) (878) (939) (878) (939) 544 683 544 683 (781) (781) (1,255) (1,255) (974) (974) (981) (981) 781781 levels of mechanization are feasible. This information is potentially useful for Kenyan policy makers, who are currently faced with difficult decisions about land use and agricultural development. Knowledge of the likely efficiency cost of breaking up large landholdings for redistribution to smallholder farmers will help inform the policy debate. Setting Agricultural Research Priorities Finally, the DRC framework can be used to help research managers decide how to allocate scarce resources between commodities, regions, or technologies. By using sensitivity analysis to vary technical parameters in the enterprise budgets, research managers can estimate the productivity gains needed to alter existing comparative advantage rankings. This information can be weighed against the probability and likely cost of achieving such productivity gains. An example of this particular use ofDRC analysis appears in Morris' (1988) study of wheat in Zimbabwe. Under a drought scenario in which water was assigned a high opportunity cost to reflect its alternative use value in tobacco production, Zimbabwe was found to lose its comparative advantage in wheat production. By implication, the introduction of more water-efficient wheat production technologies might allow the country's comparative advantage in wheat production to be maintained even in periods when water is scarce. Sensitivity analysis was used to test the effect on the comparative advantage rankings of reduced irrigation requirements. Specifically, the variable costs associated with irrigating wheat were gradually lowered to determine the irrigation level at which wheat would become competitive with other crops. Break-even analysis revealed that Zimbabwe's comparative advantage in wheat production would be maintained even during periods of drought if the crop's irrigation requirements could be reduced from the present 720 mm to around 420 mm (gross). Research managers can use this information to help decide whether or not to allocate increased resources to irrigation management research or to breeding for more drought-resistant varieties. 27 55 ProblemsCommonly Commonly Problems EncounteredininUsing UsingDRC DRCMethods Methods Encountered Before turning a discussion of the strengths weaknesses of the DRC Before turning to atodiscussion of the strengths andand weaknesses of the DRC framework, is useful to cite a number of problems commonly encountered framework, it isit useful to cite a number of problems commonly encountered in in carrying applied comparative advantage analysis. Some of these problems carrying outout applied comparative advantage analysis. Some of these problems practical in nature, while others relate more to conceptual difficulties with areare practical in nature, while others relate more to conceptual difficulties with theory underlying DRC approach. of the problems have a bearing thethe theory underlying thethe DRC approach. AllAll of the problems have a bearing on on likely accuracy of empirical research results therefore should thethe likely accuracy of empirical research results andand therefore should be be recognized analyst considering undertaking a comparative advantage recognized by by thethe analyst considering undertaking a comparative advantage study. study. Extensive Data Requirements Extensive Data Requirements Because of the extensive data requirements, applied comparative advantage Because of the extensive data requirements, applied comparative advantage analysis tends to be costly in terms of time effort. Field visits must analysis tends to be costly in terms of time andand effort. Field visits must be be undertaken early to identify enterprise substitution possibilities available undertaken early to identify thethe enterprise substitution possibilities available current (and potential) production alternatives must taken to farmers, since current (and potential) production alternatives must be be taken to farmers, since account if the alternative values of primary factors to be estimated intointo account if the alternative useuse values of primary factors areare to be estimated accurately. Once production alternatives have been identified, a detailed accurately. Once production alternatives have been identified, a detailed enterprise budget must constructed each production alternative, includenterprise budget must be be constructed for for each production alternative, includcomplete accounting fixed as well as variable costs of production. Often inging complete accounting for for fixed as well as variable costs of production. Often requires construction of separate budgets capital inputs (e.g., vehicles, thisthis requires construction of separate budgets for for capital inputs (e.g., vehicles, farm machinery, irrigation systems, barns sheds). many instances, farm machinery, irrigation systems, barns andand sheds). In In many instances, budget data already available from secondary sources, obviating budget data willwill already be be available from secondary sources, obviating thethe need primary data collection at the farm level. However, even secondary need forfor primary data collection at the farm level. However, even secondary sources must carefully verified accuracy representativeness. This sources must be be carefully verified for for accuracy andand representativeness. This a frustrating exercise, since farmers engage a wide range of produccancan be be a frustrating exercise, since farmers engage in ainwide range of producpractices typically a range of prices inputs outputs. tiontion practices andand typically faceface a range of prices for for inputs andand outputs. After enterprise budgets have been constructed inputs outputs Mter thethe enterprise budgets have been constructed andand inputs andand outputs dis-disaggregated their tradable primary factor components, complete aggregated intointo their tradable andand primary factor components, thethe complete vectors of market social prices must constructed. Market prices vectors of market andand social prices must be be constructed. Market prices cancan usually obtained directly from agricultural input suppliers other firms usually be be obtained directly from agricultural input suppliers andand other firms providing goods services to the agricultural sector, generally andand services to the agricultural sector, butbut thisthis generally providing goods requires a costly time-consuming data collection effort. Once market prices requires a costly andand time-consuming data collection effort. Once market prices have been collected, estimation of social prices requires additional knowledge have been collected, estimation of social prices requires additional knowledge of of world reference prices tradables, global transportation rates handling world reference prices for for tradables, global transportation rates andand handling costs, government import export policies, taxes, subsidies, costs, government import andand export policies, taxes, subsidies, etc.etc. times it may possible to reduce data requirements estimating social At At times it may be be possible to reduce data requirements by by estimating social prices only some inputs outputs. If market prices heavily distorted inputs andand outputs. If market prices areare heavily distorted prices for for only some a small number of highly influential policies (e.g., a vastly overvalued by by a small number of highly influential policies (e.g., a vastly overvalued exchange rate, producer prices that way of line with world equivalent exchange rate, producer prices that areare way outout of line with world equivalent prices, large subsidies fertilizers), reasonably accurate comparative advanprices, large subsidies on on fertilizers), reasonably accurate comparative advantage rankings sometimes obtained adjusting only those policies tage rankings cancan sometimes be be obtained by by adjusting for for only those policies ignoring other price distortions. Common sense help in identifying andand ignoring all all other price distortions. Common sense cancan help in identifying highly influential policies, a priori there is no way of knowing with thethe highly influential policies, butbut a priori there is no way of knowing with 28 28 certainty which distortions alter comparative advantage rankings. As the Zimbabwe case study shows, some government policies affect all enterprises more or less equally, which may decrease or increase private profitability relative to social profitability but may not alter comparative advantage rankings. In summary, the extensive data requirements of the DRC methodology suggest that DRC analysis should not be undertaken if the researcher is unable or unwilling to invest considerable time and effort in data collection activities. Efforts to cut corners, for example by failing to cost out all major production alternatives or by guessing at important opportunoty costs, may seriously affect the quality of the research results. Determining Social Prices for Primary Factors A recurring problem in DRC analysis involves the estimation of social prices for primary factors. As discussed earlier, social prices for primary factors are supposed to represent the true economic value of these factors in the economy. This is usually estimated as the opportunity cost value, i.e., as the value of the factor in its most profitable alternative use. While the concept of alternative use value is straightforward in principle, in practice each type of primary factor presents its own unique estimation problems. The importance of accurately estimating the social price of land cannot be overemphasized, since this price frequently is decisive in determining comparative advantage rankings. As mentioned previously, a reasonable approximation of the opportunity cost of land can be obtained from the enterprise budgets themselves as the net social returns to land in the most socially profitable cropping alternative. (One advantage of this approach is that it automatically removes policy distortions on competing crops.) In most of the CIMMYT studies, this value has been found to differ significantly from the market price ofland (annualized purchase price or rental value). However, if the enterprise budgets are to be used for estimating the social price of land, it is important that all reasonable production alternatives be identified and costed out. As mentioned earlier, a glaring weakness of many DRC studies is that they focus on one enterprise of immediate interest and fail to consider alternative enterprises. Social prices of land therefore do not accurately reflect alternate use values, and comparative advantage findings may be seriously distorted. Estimating accurate social prices for labor can also be important in DRC analysis, especially when production alternatives differ significantly in their labor requirements and there is evidence that the labor market is distorted. Typically this occurs when government policies (e.g., minimum wage legislation) have raised the market price of agricultural labor above the true marginal value product. Several methods have been developed for formally calculating the shadow wage rate of agricultural labor (see McDiarmid 1977; Gittinger 1982). Alternatively, the DRC analyst may simply want to adjust market wage rates with the help of a conversion factor obtained from published studies, 29 assuming these exist. Sensitivity analysis should then be carried out to determine the importance of the social price assigned to labor. If the final comparative advantage rankings are found to be highly sensitive to the price assigned to labor, this should be reported. The problems inherent in estimating the real opportunity cost of capital are well known and have been discussed elsewhere (for example, see Gittinger 1982). For DRC analysis, it is usually not worth spending a lot of time and effort estimating the opportunity cost of capital unless the value selected is likely to have a decisive effect on the comparative advantage rankings. (This might be the case when potential production alternatives differ drastically in capital-intensiveness, e.g., a highly mechanized technology vs. a labor-intensive technology). Therefore, before any calculations are undertaken, it is wise to carry out sensitivity analysis to determine the importance of the social price assigned to capital. If comparative advantage rankings are found to be robust with respect to the opportunity cost of capital, an informed "guesstimate" will probably be satisfactory. In some instances a primary factor other than land, labor, or capital will represent the limiting factor in production, and it will be necessary to estimate a social price for this factor as well. For example, in the Zimbabwe wheat study, irrigation water was determined to be the limiting factor of production during drought years. Since calculation of the marginal value product of production inputs is usually impractical (especially in the presence of policyinduced distortions), it will often be necessary to resort to less rigorous approximations to estimate an alternative use value. In the Zimbabwe study, an average value of irrigation water was calculated based on the difference in profitability between rainfed and irrigated production--not a very exact approximatio~ of the marginal value product, but almost certainly better than the naive assumption of no difference in the value of water between normal rainfall years and drought years. (Alternatively, a simple linear programming model of a representative irrigated farm could have been used to calculate the shadow price of irrigation water.) To recapitulate, estimation of social prices for primary factors tends to be difficult in practice and often requires use of imperfect approximation techniques. Sometimes it will be possible to demonstrate through sensitivity analysis that the comparative advantage rankings are robust with respect to the social prices assigned to primary factors, but frequently the rankings will be sensitive to changes in social prices. In such cases, it is important to report the results of the sensitivity analysis to aid in the interpretation of research findings. 30 Determining Social Prices for Non-traded Tradables Problems sometimes arise in establishing social prices for non-traded tradables. Non-traded tradables typically appear when transportation and handling charges involved in getting a commodity to and from world markets introduce a wide gap between the import and export parity prices. Whenever the domestic price lies within this gap, importing and exporting will both be uneconomical. For example, in the country depicted in Figure 1, domestic supply of wheat equals domestic demand at P E and QE' Because of high transport and handling costs involved in gaining access to world markets, trade in wheat will be uneconomical; the import parity price is too high to induce consumption of imports, and the export parity price is too low to encourage additional production for export. How should social prices be determined for non-traded tradables? If the market price is an undistorted market-clearing price that effectively equilibrates domestic supply and demand (as in Figure 1), the market price accurately reflects the product's economic value and can be used as an approximation of the social price. But if the market price reflects distortions due to policy effects or market failure, an adjustment should be made to arrive at the social price. In Figure 2, government policies have introduced a gap between the controlled market price (Pc) and the theoretical market-clearing equilibrium price (PE)' In this example, the controlled market price (Pc) has been set lower than the theoretical market-clearing equilibrium price (P E)' and demand (QD) therefore exceeds supply (Q~). The government can react to this excess demand in two ways: 1) by doing nothing and allowing the excess demand to persist, or 2) by importing the additional quantity necessary to satisfy demand at the controlled price and selling it to consumers at a loss (represented in Figure 2 by the shaded area). Whatever the government's reaction, the difference between P E and Pc represents a policy-induced distortion which should be eliminated for DRC analysis. The appropriate correction is to estimate a social price equal to the theoretical market-clearing price (PE)' (Note that even though the government's response may be to import QD-QS at the import parity price, it is incorrect to set the social price equal to the import parity price--a common error in the literature, especially when trade is taking place--since in the absence of price controls domestic supply would increase to satisfy demand at a price well below the import parity price.) 31 Price P import parity P export parity Demand o QE Quantity Figure 1.Conditions giving rise to a non-traded tradable. Price P import parity PE 1 - - - - - - - Pc 1 - - - - - - - - - - : 0 Pexport t---~--+---+-----+------+----~-~ parity Demand o Quantity Figure 2. Establishing social prices for non-traded tradables. 32 Estimating an Equilibrium Exchange Rate Since the exchange rate used to convert between domestic and foreign currencies affects the social prices of all tradables, it is important that exchange rate distortions be properly identified and corrected for purposes of DRC analysis. Estimating an accurate real equilibrium exchange rate can present major problems. Among other things, the issue may be politically sensitive; government officials in many developing countries are reluctant to acknowledge, much less discuss, exchange rate over- or undervaluation. Even when the issue can be discussed openly, often there is no easy way to estimate the degree of exchange rate distortion. Ifno reliable estimates of the real equilibrium exchange rate are available from secondary sources, a formal estimation procedure may have to be undertaken. The purchasing power parity (PPP) method is usually the simplest. The most basic version of the PPP method involves selecting a base year in which the official exchange rate is judged to have been valued at its true equilibrium rate in relation to the currency used by the dominant trading partner (often the US dollar) and deflating the official exchange rate in subsequent years by the difference in domestic inflation rates: where: E* E = real exchange rate nominal exchange rate (units of domestic currency per unit of foreign currency) price deflator for domestic currency price deflator for foreign currency = = = An improvement on this basic version of the PPP method is to calculate a trade-weighted equilibrium exchange rate, essentially a composite exchange rate calculated against a basket of foreign currencies, weighted according to actual trading patterns: ET* = where: ET* Ew = = = = = = real trade-weighted exchange rate nominal exchange rate (units of domestic currency per unit of currency in country w) value of trade with country w value of total trade price deflator for domestic currency price deflator for currency in country w 33 Alone, PPP methods may be inadequate for estimating the equilibrium exchange rate. The existence of trade barriers (e.g., import quotas that drive up the cost of imported goods, or high tariff protection for domestic industries) can make selection of a base year problematic unless additional adjustments are made. Several more sophisticated methods for calculating the equilibrium exchange rate have been described in the literature (see Dornbusch and Helmers1988; Krueger, Schiff, and Valdes 1988; Ward 1976). No particular method is advocated here, since much will depend on the availability of data and the resources for analysis. Predicting General-Equilibrium Effects One criticism sometimes directed at the DRC approach concerns the difficulty of predicting general-equilibrium effects, both on the output side and on the input side. The criticism is valid, since the RCR for a particular enterprise does not indicate how much incremental production can be absorbed by the economy before prices are affected. In certain instances, changes in production patterns are likely to have significant effects on prices. For example, if potato production were to increase dramatically in Ecuador, the domestic market would soon be saturated and potato prices would fall. This would affect the net social profitability of potato production, because potatoes in Ecuador are classified as a nontraded tradable, and the market price is equivalent to the social price. Conventional DRC analysis fails to consider this likely general-equilibrium effect. Similarly, DRC analysis assumes fixed factor prices, under the implicit assumption that changing patterns of production would have no effect on factor prices in the future. This assumption may be unrealistic. For example, if tobacco production were to increase dramatically in Zimbabwe, shortages of labor could be expected to develop during harvesting, which would result in upward pressure on wage rates. Once again, conventional DRC analysis fails to take this likely general-equilibrium effect into account, since it assumes that wage rates remain constant regardless of the quantity oftobacco produced. Before attempting to incorporate general-equilibrium effects into the DRC framework, it is important to recognize the tradeoff between realism and practicality. While the DRC framework described in this paper admittedly is based on a partial-equilibrium approach, it is precisely this feature which makes DRC analysis practical. Realism in the form of general-equilibrium effects (as in multi-market simulation models) can be introduced only at the expense of increased complexity, which may make the results unintelligible to many policy makers. If important general-equilibrium effects are anticipated, however, these can be incorporated into DRC analysis in several ways. The simplest approach is to judge whether or not enterprises which currently are socially profitable offer viable production alternatives with real possibilities for expansion. If the answer is clearly no (because of constraints on either the input or the output 34 side), these enterprises should be eliminated from further consideration. Thus, although potato production was the most socially profitable enterprise in Ecuador, clearly the market for Ecuadoran potatoes is limited, and potatoes should not receive high priority in the allocation of scarce research resources. If the answer is uncertain, sensitivity analysis can help indicate whether a crop's current ranking would be threatened by possible future changes in input or output prices. If social profitability levels turn out to be highly sensitive to one or more prices whose future levels remain uncertain, it may be appropriate to carry out a formal market study, including price projections. Comparative Advantage vs. Competitive Advantage A number of critics have pointed out that the DRC approach does not really measure comparative advantage, since social profitability levels and RCRs are calculated using world reference prices which may themselves reflect significant policy-induced distortions. (For example, USDA estimates that the world price of wheat has been maintained approximately 33% below the level which would prevail in the absence of the farm support policies and export enhancement programs of the industrialized countries.) Consequently, rather than providing a true measure of relative efficiency in production, DRC analysis merely generates a measure of one country's ability to compete with prevailing world prices. Put another way, this means that DRC does not measure comparative advantage, but rather competitive advantage. While technically correct, this criticism of the DRC approach does not affect its usefulness for policy-making. If price distortions in world markets are expected to continue, the social price oftradables is correctly estimated as the long-term world reference price, since this represents the effective opportunity cost value oftradables to the economy. Consequently, policy decisions based oli DRCgenerated comparative advantage rankings retain their validity. 35 6 Lessons From the CIMMYT Case Studies During the past decade, concern for agricultural policy reform in many developing countries has generated renewed interest in empirical measurement of patterns of comparative advantage. One consequence has been a rapid proliferation of DRC studies, since the DRC framework provides a practical approach for generating quantitative measures of comparative advantage. This paper has reviewed the DRC methodology and presented examples illustrating different applications of the DRC approach. In closing, it seems appropriate to reflect upon the usefulness of applied comparative advantage analysis for CIMMYT and for our clients in the national agricultural research systems, as indicated by the reception that the case studies have received. CIMMYT's original decision to undertake a series of applied comparative advantage studies was motivated by an interest in developing methods to help the decision making of research administrators in national agricultural research systems (Longmire and Winkelmann 1985). The idea was that research administrators would be able to allocate resources more efficiently if they had knowledge of patterns of comparative advantage--between crops, between regions, or between alternative production technologies. Thus, DRC analysis was seen as a way of generating the sort of information which would help the director of a national research program decide whether to launch a new project in small grains or in oilseeds, whether to build a research station for wheat in Region A or in Region B, or whether to hire an irrigation scientist or a rainfed crop specialist. To what extent have the CIMMYT DRC studies been able to generate this sort of information? While most of the studies have generated results which could help inform research resource allocation, many of the studies apparently have failed to elicit the anticipated interest among research administrators in the national systems. One possible reason for this apparent lack of interest may be that the connection between DRC analysis and research resource allocation is not always obvious. Many research managers simply may not know what to do with the efficiency indicators generated by DRC analysis, especially since research policy is not driven exclusively by efficiency considerations. Given that non-efficiency considerations frequently enter into research priority setting, the link between DRC analysis and research resource allocation becomes quite complex. To see this, consider the three hypothetical enterprises depicted in Figure 3. Each enterprise is assigned two social profitability levels-one calculated on the basis of existing technology (SPo)' and one estimated on the basis of improved technology expected to become available after investment in agricultural research (SP ). For all three enterprises, social profitability under "improved technology~' is higher than social profitability under "existing technology." However, the absolute values of the social profitability levels differ between the three enterprises, as do the changes in social profitability resulting from investment in agricultural research (DSP, represented by the length of the arrows). Enterprise 1 is socially profitable under current technology and becomes even more socially profitable under improved technology, although the 36 Social profitability + o Enterprise 1 Enterprise 2 Enterprise 3 Figure 3. Using DRC analysis for research resource allocation. increase in profitability is small. Enterprise 2 is not socially profitable under current technology, although it becomes socially profitable under improved technology as the result of a medium increase in profitability. Enterprise 3 is not socially profitable under current technology or under improved technology, despite a large increase in profitability (actually a decrease in unprofitability). Which enterprise merits highest priority with regard to research investment? The answer depends on a number of considerations, including: • the importance of non-efficiency considerations in setting research policy (e.g., projected distributional impacts oftechnological change across regions or income classes; food security objectives); • the size of the total agricultural research budget (which determines how many enterprises can be worked on simultaneously); • the relative costs of different kinds of research programs (which might vary considerably among the three enterprises) 37 • • the theconfidence confidenceofofresearch researchadministrators administratorsthat thatSP SP1 1has hasbeen beenestimated estimated correctly correctly(which (whichmay mayrequire requirestrong strongassumptions assumptionsabout aboutthe thefuture futureimpact impact ofoftechnologies technologiesstill stilltotobe bedeveloped); developed); • • the theperceived perceivedlikelihood likelihoodthat thatfarmers farmerswill willbe bewilling willingand andable abletotosubstisubstitute tuteone oneenterprise enterprisefor foranother anotheronce oncethe theimproved improvedtechnology technologyisis available; available; • • the thelevel levelofofconfidence confidenceininprojections projectionsofoflikely likelyfuture futuredevelopments developmentsininthe the global globaleconomy economy(e.g., (e.g.,supply supplyand anddemand demandofofparticular particularcommodities; commodities; world worldprices); prices); • • the theprobability probabilitythat thatpolicy-induced policy-induceddistortions distortionswill willbe beremoved removed(which (which may mayeliminate eliminatesocially sociallyunprofitable unprofitableenterprises enterprisessuch suchasasEnterprise Enterprise3). 3). Given Giventhese theseconsiderations, considerations,ititisispossible possibletotoconceive conceiveofofsituations situationsininwhich whichitit would wouldbe bedesirable desirabletotoinvest investininresearch researchon onanyone anyoneofofthe thethree threeenterprises, enterprises,oror totoinvest investininresearch researchon onvarious variouscombinations combinationsofofthe thethree. three.This Thismerely merelyserves serves totoemphasize emphasizethat thatthe theefficiency efficiencyindicators indicatorsgenerated generatedby byDRC DRCanalysis analysisdo donot not provide provideunambiguous unambiguousinvestment investmentguidelines guidelinesfor forresearch researchmanagers. managers.Provided Provided they theyare areused usedcarefully, carefully,DRC DRCresults resultscan canserve serveasasaabasis basisfor forranking rankingenterenterprises prisesininterms termsofofcurrent currentand andexpected expectedfuture futuresocial socialprofitability, profitability,asaswell wellasasfor for segregating segregatingthose thoseenterprises enterprisesthat thatwaste wasteforeign foreignexchange exchangeorordomestic domesticcurcurrency. rency.Through Throughsensitivity sensitivityanalysis, analysis,DRC DRCresults resultscan canalso alsohelp helpindicate indicatethe thesize size ofofchanges changesininfuture futureprices pricesorortechnologies technologieslikely likelytotoalter altercurrent currentpatterns patternsofof comparative comparativeadvantage. advantage.However, However,DRC DRCanalysis analysisisisnot notaa"cookbook" "cookbook"method methodfor for mechanically mechanicallycranking crankingout outresource resourceallocation allocationrules. rules.Rather, Rather,the theDRC DRCframeframework workgenerates generatesone onetype typeofofinformation informationwhich whichmust mustbe becombined combinedwith withother other types typesofofinformation informationtotoinform informthe thedecision decisionmaking makingofofpolicy policymakers makersand andreresearch searchmanagers. managers.The Thechallenge challengewill willbe betotodevise devisemethods methodsfor fortranslating translatingthe the information informationgenerated generatedby byDRC DRCanalysis analysisinto intoaaform formininwhich whichititisismore moreaccesaccessible sibletotoresearch researchmanagers. managers. Yet Yetififthe theCIMMYT CIMMYTcomparative comparativeadvantage advantagestudies studieshave havefailed failedtotogenerate generatethe the expected expectedinterest intereston onthe thepart partofofresearch researchmanagers, managers,they theyhave havebeen beenwell wellrereceived ceivedby byothers. others.The Theresults resultsgenerated generatedby byindividual individualcase casestudies studies(both (boththe the comparative comparativeadvantage advantagerankings rankingsand andespecially especiallythe theresults resultsofofcomparative comparative profitability profitabilityanalysis) analysis)frequently frequentlyhave havebeen beenseized seizedby byproducer producergroups groupsand/or and/or government governmentofficials officialstotobe beintroduced introducedasasevidence evidenceininthe thepolicy policydialogue. dialogue.This This has hashappened happenedeven eventhough thoughthe theauthors authorshave havemade madelittle littleeffort efforttotopublicize publicizethe the policy policyimplications implicationsofofthe theresearch researchfindings, findings,since sinceCIMMYT CIMMYThas hasnot notsought soughttoto participate participatedirectly directlyinindomestic domesticagricultural agriculturalpolicy policydebates. debates. 38 38 Our experience suggests that comparative advantage studies can help inform the policy dialogue in two important ways. First, social profitability analysis reveals how government policies influence agricultural production incentives. Knowledge of the distribution and strength of policy-induced price distortions can be extremely valuable in helping policy decision-makers make desired adjustments, especially knowledge about the relative importance of targeted taxes and subsidies (e.g., producer price controls, subsidies on inputs) vs. general economy-wide policies (e.g., labor policy, exchange rate policy). Very few other analytical methods reveal these effects in such easily intelligible terms. Second, social profitability measures and RCRs are quantitative indicators of comparative advantage which can help decision-makers to assess the cost of promoting one set of production activities at the expense of another. It is important to recognize, of course, that comparative advantage rankings are based on economic efficiency alone and fail to take into account non-efficiency considerations, which often figure prominently in the policy debate (e.g., income distribution, food security, sustainability). In this respect, DRC analysis clearly must be seen as only one tool for applied policy analysis. Nevertheless, most agricultural policy decisions start with an assessment of the economic costs and benefits of alternative courses of action, and the advantage of the DRC framework is that it provides quantitative measures of the opportunity cost of pursuing different alternatives. The DRC framework thus represents an important element--although certainly not the only element--in the policy analyst's conceptual tool kit. An additional point that should be made concerning the practical utility of the DRC approach is the tremendous flexibility introduced by micro-computer technology. Once enterprise budgets and price vectors have been developed and recorded in a computerized spreadsheet program, adjustments can easily be made to reflect changes in technology or prices. Social profitability measures and RCRs can then be calculated on an annual basis (or more frequently if desirable) to obtain a dynamic picture of evolving changes in patterns of comparative advantage. This is obviously very attractive to policy analysts, since it means that once the initial work of calculating RCRs is completed, comparative advantage rankings can subsequently be updated at little additional cost. Final.lY, the CIMMYT comparative advantage studies have provided a practical lesson in the dynamics of policy reform. It has become clear from the case studies that the use of comparative advantage results ultimately depends to a large extent on who is perceived as having carried out the analysis. When information on comparative advantage is needed to appraise a proposed project loan, it probably matters little who actually does the calculations, whether a local economist or an expatriate "expert" brought in from outside. But if DRC results are to have an effect on domestic policies, in practice it seems to matter 39 a great deal who does the analysis. Comparative advantage studies by nature tend to be politically controversial, because among other things they reveal the distributional effects of government policies. Such information can be invaluable in the policy dialogue, but only if it is introduced by someone who is able to playa forceful role in arguing for policy reform. What this means is that often it will not be appropriate for comparative advantage studies to be carried out by expatriate scientists, especially scientists working for international research centers which have no desire to become directly involved in domestic policy debates. Scientists in international agricultural research centers can offer training in DRC methods to local researchers, as well as technical assistance in carrying out applied DRC studies, but it is the local researchers themselves who must take the lead in conducting the studies and publicizing the results. For only if a strong local advocate is willing to take a stand in the policy debate are the research results likely to make a difference. 40 References Byerlee, D. 1989. Bread and butter issues in Ecuadoran food policy: A comparative advantage approach. World Development 17(10). Byerlee, D. 1985. Comparative Advantage and Policy Incentives for Wheat Production in Ecuador. CIMMYT Economics Program Working Paper 01/85. Mexico, D.F.: CIMMYT. Byerlee, D., and J. Longmire. 1986. Comparative Advantage and Policy Incentives for Wheat Production in Rainfed and Irrigated Areas of Mexico. CIMMYT Economics Program Working Paper 01186. Mexico, D.F.: CIMMYT. Dornbusch, R., and L. 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