Values of Time and Vehicle Operating Costs
TAG Unit 3.5.6
January 2014
Department for Transport
Transport Analysis Guidance (TAG)
This Unit is part of a family which can be accessed at www.dft.gov.uk/webtag
Contents
1
Introduction
1
2
Values of Travel Time Savings
2
2.2
2.3
2.4
2.5
Values of Working Travel Time Savings per Person
Values of Non-Working Travel Time Savings per Person
Annual Rates of Growth in Values of Travel Time Savings
Values of Travel Time Savings per Vehicle
2
6
8
11
3
Vehicle Operating Costs
17
3.2
3.3
3.4
Vehicle Operating Costs – Fuel and Electricity
Vehicle Operating Costs – Non-Fuel
Public Transport Operating Costs
17
27
30
4
Further Information
31
5
References
31
6
Document provenance
32
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
1
Introduction
1.1.1
This TAG Unit provides the latest values of time, occupancy figures, purpose splits, GDP
growth rates and vehicle operating costs recommended by the Department for Transport
(DfT) for use in economic appraisals of transport projects in England, as well as the rest of
Great Britain with the relevant Overseeing Organisation’s permission.
1.1.2
The values presented in this Unit are included in the TUBA computer program, for which
further advice may be obtained from the DfT.
1.1.3
This Unit aims, as far as possible, to cover all modes of transport. However in certain parts
of the Unit, notably vehicle occupancies and vehicle operating costs, a lack of available
data means that not all modes have been covered.
1.1.4
Revision of the March 2001 TEN was necessary to allow implementation of the
recommendations contained in the latest research for the DfT on valuation of non-working
travel time savings (Values of Travel Time Savings in the UK, Institute for Transport
Studies, University of Leeds, 2003). 1
1.1.5
Important note for those using these values in modelling: In 2012, HM Treasury
altered its GDP deflator to be based on the Consumer Prices index (CPI) rather than the
Retail Prices Index (RPI) as used in the previous version of this Unit. This means that the
annual GDP growth values in real terms in this unit are approximately 0.2 percentage
points higher than they would have been in previous versions of the unit. Analysts should
consider what implications this change has for their models. Some models, particularly
those calibrated on historic GDP growth over more than one year, may need to be
recalibrated or (eg rail models using the elasticities given in the Passenger Demand
Forecasting Handbook) may require an adjustment to the GDP series used in forecasting,
by reducing the GDP growth values given in this Unit by 0.2 percentage points per annum.
For cross-sectional models (which are calibrated based on data for one historic year only),
or on forecasts based primarily on population growth (eg NTEM), it should be possible to
use the values of time given in this unit without adjustment. Note that the values of time
used for appraisal purposes should not be affected, regardless of the type of model.
Methods of Cost Benefit Analysis
1.1.6
Cost benefit analysis aims to take account of all the ways in which a project affects people,
irrespective of whether those effects are registered in conventional financial accounts. The
method of cost benefit analysis for appraisal is the calculus of 'willingness to pay' using a
market price unit of account. A full discussion of the methodology is given in Cost Benefit
Analysis (TAG Unit 3.5.4).
Units of Account
1.1.7
The market price unit of account expresses prices in market prices. Market price refers to
the price paid by consumers for goods and services in the market and therefore includes all
indirect taxation (indirect taxation refers to taxation levied on a product and therefore
includes excises, duties and VAT). Prices that do not include taxation (e.g. public transport
fares) are still perceived by consumers in the market price unit of account.
1
The Department is consulting on the use of segmented values of time for road pricing and tolling studies only
(see TAG Unit 3.12C) because, in those circumstances, there may be substantial changes in the monetary
costs of travel. In all other circumstances the values given in Tables 1 and 2 in this TAG Unit should be used
for project appraisal.
Page 1
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
1.1.8
The factor cost unit of account expresses prices in resource costs. Resource costs are
costs that are net of indirect taxation. The prices paid by Government for goods and
services are not subject to indirect taxation as any tax that is paid by Government bodies
such as the Highways Agency is recovered by Government and thus may be ignored.
Government expenditure is therefore in the factor cost unit of account. Business costs and
benefits are also assumed to be in the factor cost unit of account as businesses are free of
indirect taxation because they can claim it back. An exception to this is fuel duty, which
businesses cannot claim back.
1.1.9
Costs can be converted to (or from) market prices by multiplying (or dividing) by the indirect
tax correction factor, (1+t), where t is 19.0% - the average rate of indirect taxation in the
economy. This rate is based on data from HMRC and replaces the previous value of
20.9%.
1.1.10 Perceived costs are those which are actually experienced by users. Perceived costs are
different for work and non-work trips because businesses can claim back VAT on
purchases. Businesses cannot, however, claim back fuel duty and therefore this is included
in their perceived cost. (N.B. certain classes of PSV can claim back fuel duty. This should
be treated as a subsidy). Note that business users perceive costs in the factor cost unit of
account, while consumers perceive costs in the market price unit of account.
2
Values of Travel Time Savings
2.1.1
This section provides the latest values of time recommended by the DfT for use in most
routine economic appraisals of transport projects. All items are expressed in average 2010
values and prices.
2.1.2
The Department accepts that different values of time may be needed in other
circumstances, such as appraisal of strategic analysis, road user charging and toll roads.
The Department will issue further guidance on appropriate values and methods to use for
these appraisals. For most routine appraisals the guidance in this document is relevant.
2.2
Values of Working Travel Time Savings per Person
Estimating willingness-to-pay for working travel time savings
2.2.1
Businesses benefit from reduced travel times in a number of ways, including improved
access to suppliers or customers, which increase productivity by lowering the cost or
raising the quality of inputs and widening the market which a business can serve.
Therefore, it follows that businesses should be willing to pay for quicker journeys and it is
this willingness-to-pay which forms the basis of values of working travel time savings.
2.2.2
There are many real world situations where business travellers choose to pay more for a
quicker journey when a cheaper, slower alternative is available. For example, surveys
found that around one third of M6 toll road users are travelling on employers’ business and
they stated that saving time compared to alternative routes was their main reason for using
the toll road 2 .
2.2.3
Market prices are often used to represent willingness-to-pay in cost-benefit analysis.
However, although examples exist where travellers trade travel time for cost, market prices
for travel time are not easily obtainable and, in the absence of market prices, alternative
techniques are required to estimate willingness-to-pay. There are a range of approaches
2
M6T Research Study – Stage 2 Utilisation Surveys, Faber Maunsell / AECOM (2008):
https://www.gov.uk/government/publications/utilisation-surveys
Page 2
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
available and, while the techniques, assumptions and resulting values vary, all of the
methods aim to estimate values that effectively proxy for willingness-to-pay.
2.2.4
Revealed preference evidence is the most direct way to estimate willingness–to-pay, and is
based on actual business traveller behaviour (for example, surveys of users of the M6 toll
road and alternative routes). However, it is difficult to collect revealed preference data of
sufficient quality and quantity to estimate robust values and provide the detail needed to
fully populate a framework of values. In the absence of revealed preference evidence of
sufficient quality, it is necessary to use alternative methods and techniques to estimate
values.
2.2.5
The Department’s approach is to take account of all the relevant evidence available and to
seek to make reasonable judgments, in light of economic theory. This includes the
information available on distance-weighted average hourly incomes of business travellers.
Evidence of willingness-to-pay for working travel time savings
2.2.6
The Department commissioned a review of the different methods, including a review of UK
and international evidence on the values they produce: Valuation of Travel Time Savings
for Business Travellers, by the Institute for Transport Studies, University of Leeds (ITS
Leeds) 2013. Alongside revealed preference evidence and the Department’s current
approach, this review considered stated preference evidence collected from survey
responses to realistic hypothetical choices, and the ‘Hensher’ approach, which builds on
the Department’s current approach with explicit assumptions about how travel time is used.
2.2.7
The review provides valuable insights on businesses’ willingness-to-pay for travel time
savings, but also raised concerns about inconsistencies and uncertainties in the current
evidence base. Figure 1 summarises values from this review along with the car driver and
rail passenger values recommended for use in transport appraisal in this TAG Unit
(labelled “WebTAG values”). The figure also provides ranges around the values to indicate
the degree of confidence in the estimates.
2.2.8
The figure shows a wide range of values, with significant variation in estimates across the
techniques, modes of transport analysed and study locations. The wide ranges around the
revealed preference data result from the small number of available studies and reflect the
difficulties in obtaining this data. The “WebTAG values” are towards the centre of the range
of values and correspond closely with the average values from the available revealed
preference evidence. Based on this summary of the current evidence, the Department is
firmly of the view that the “WebTAG values” presented in Table 1 below, represent a
reasonable estimate of willingness-to-pay for travel time savings in the course of work.
Page 3
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Value of travel time savings (£/hour, 2010 prices)
Figure 1 – Values of travel time savings in the course of work resulting from different
valuation techniques
100
RP - UK all modes
RP - non-UK all modes
Car values
Rail values
UK High Speed Rail
WebTAG - car
WebTAG - rail
90
80
70
60
50
40
30
20
10
0
Revealed
preference
UK stated
preference
*
non-UK stated
preference
Hensher
approach
WebTAG values
Sources: Valuation of travel time savings for business travellers, ITS Leeds, 2013; and DfT analysis
Notes:
* ITS Leeds’ report raised concerns over the approach taken in many UK Stated Preference studies to explaining how
company travel policy should be considered and who should be assumed to pay for, and benefit from, travel time savings.
There is therefore a concern that the values could reflect more personal, than business valuation, likely leading to a
downward bias in the values shown in the chart.
1. The solid line error bars represent robustly calculated confidence intervals. The dotted lines are indicative representations
of potential variability as the sample sizes are not sufficient to support calculation of formal confidence intervals.
2. Revealed preference data are taken directly from the ITS report, with the ranges based on the reported standard errors.
3. The Stated preference data for UK car and non-UK rail and car are derived by pooling the urban and inter-urban “valued”
data from the ITS report. The mean values have been calculated on a travel time-weighted average basis, with 2008-10
National Travel Survey data, with the ranges calculated as the weighted average standard error. The SP data for UK rail are
based on the mean and standard errors reported for inter-urban rail “valued” due to the very small number of UK urban rail
studies.
4. The High Speed Rail values are based on the 3 reports covered by ITS Leeds most relevant to the UK domestic HSR
market: Bates (2012), Atkins (2009) and SDG (2002). The range is based on the standard error of the mean of 5 values
from these studies, meaning the sample is too small to be considered a robust, formal confidence interval.
5. The Hensher approach values are calculated using the parameters included in the ITS report and the values given in
Table 1. The range represents the range of parameter values recommended in sensitivity testing in ITS Leeds’ report.
6. The WebTAG values have been calculated with data from the 2008-2010 National Travel Survey, 2009 Labour Force
Survey and 2008 Labour Cost Survey. The range around them represents the +/-25% sensitivity testing recommended in
this unit.
Recommended values and sensitivity tests
2.2.9
Table 1, below, provides the values of working travel time savings per person, by mode,
that should be used in transport appraisal. In some circumstances it may be appropriate to
make the simple assumption of a common working value of time for all travellers. Where
this approach is followed, the average value for all workers should be used with sensitivity
tests carried out using the values disaggregated by mode.
Page 4
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 1 Values of Working Time per person (£ per hour, 2010 prices
and values)
Resource
Cost
Perceived
Cost
Market
Price
Car driver
Car passenger
LGV (driver or passenger)
OGV (driver or passenger)
PSV driver
PSV passenger
Taxi driver
Taxi/Minicab passenger
Rail passenger
Underground passenger
Walker
Cyclist
Motorcyclist
22.74
17.25
10.24
12.06
12.32
13.97
10.89
21.96
26.86
22.08
17.54
17.47
19.42
22.74
17.25
10.24
12.06
12.32
13.97
10.89
21.96
26.86
22.08
17.54
17.47
19.42
27.06
20.52
12.18
14.35
14.66
16.63
12.96
26.13
31.96
26.28
20.88
20.78
23.11
Average of all working
persons
22.75
22.75
27.07
Vehicle Occupant
2.2.10 The wide range of values resulting from different approaches presented in Figure 1 shows
the uncertainty around the values of travel time savings in the course of work and analysts
should undertake sensitivity tests to demonstrate the sensitivity of the appraisal results to
the value used.
2.2.11 Where specific evidence is not available, or where business time savings form a relatively
small proportion of total benefits, a sensitivity test of +/-25% of the values given in Table 1
may be used, based on the tests recommended in ITS Leeds’ report. While this does not
encompass the full range of values resulting from ITS Leeds’ review, it is sufficiently wide
to reflect the range of values resulting from the different approaches used to estimate
willingness-to-pay.
2.2.12 For simplicity and proportionality, this test can be applied as an adjustment to the present
value of time saving benefits for business travellers. As the key uncertainty around
willingness-to-pay for travel time savings relates to business passengers, rather than
professional drivers, time savings for goods vehicles and other freight modes should not be
included in the sensitivity testing.
2.2.13 Where specific willingness-to-pay evidence is available, sensitivity tests should represent
the uncertainty around the willingness-to-pay of business travellers most affected by the
scheme. The tests should be developed with evidence from studies relating to the modes
of transport and market (e.g. urban or long-distance trips) most relevant to the scheme.
Useful sources of information for developing sensitivity tests may include ITS Leeds’
evidence review in Valuation of Travel Time Savings for Business Travellers or studies
undertaken as part of development of the transport model used to assess the scheme.
2.2.14 Where specific evidence is used to inform sensitivity tests, both ‘high’ and ‘low’ tests should
be developed (that is, using values both greater and smaller than those given in Table 1).
In such circumstances, analysts should contact TASM division, DfT to agree the
appropriate range of values to be tested.
Page 5
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Box 1: Future development of values of working time
In their report Valuation of Travel Time Savings for Business Travellers, 2013, ITS Leeds
set out a number of options for development of the values of travel time savings in the
course of work. Due to the uncertainties and inconsistencies in the existing evidence, the
Department believes that fresh empirical evidence on business travellers’ willingness-topay for travel time savings is required.
The Department plans to undertake research to collect new evidence of business
travellers’ willingness-to-pay for travel time savings, which will improve our understanding
of the current uncertainties and result in future revisions to the values and ranges provided
in this Unit.
Before undertaking any new research, the Department will engage widely with
stakeholders on the methods and valuation techniques which merit further investigation
and the form this research should take.
2.2.15 The values in Table 1 apply to journeys made in the course of work and this excludes
commuting journeys. Businesses perceive travel costs in the factor cost unit of account so
the perceived cost and resource cost are the same for values of working time. The values
in the market prices unit of account, which have been adjusted with the indirect tax
correction factor, should be used in appraisal.
2.2.16 In appraisal, travel time savings on employer’s business are valued the same regardless of
the stage of the journey, e.g. there is no weighting to take account of passengers’
reluctance to walk or wait. For staged journeys, the value of working time for the main
mode (with the longest distance) should be used.
2.2.17 Using different values for each mode may appear to introduce inconsistency in appraisal
since it suggests that those switching modes change their values of time. However, this is
not the case because for any group (bus passengers, car drivers etc.) there will be a
distribution of values around the average value for the group and the distributions for each
group are likely to overlap. Therefore, the value of time for an individual within a group
need not be the average value for that group and, when they switch mode, the individual
will take up a different position in the distribution of values of time for their new mode,
compared with that for their old mode. For example, a car driver with an above average
value of time for car drivers could switch to rail, where their value of time might be below
average.
2.2.18 Large changes between modes might alter the modal distributions sufficiently to
significantly change the average values in the ‘without scheme’ and ‘with scheme’ cases.
An alternative approach is to segment travellers by income group in the transport model, so
that the average values of time for each mode are outputs of the modelling process, rather
than inputs to the appraisal. This is discussed in more depth in Modelling (TAG Unit 3.1). In
circumstances where switching is high compared to the number of existing users, analysts
should contact TASM Division, DfT for further advice.
2.3
Values of Non-Working Travel Time Savings per Person
2.3.1
The majority of journeys do not take place during working hours, but in the traveller’s own
time. However, people implicitly put a value on their own time, in that they will trade a
cheaper, slower journey against a faster, more expensive one. It is therefore appropriate to
take account of this value in assessing the impact of different transport strategies or plans.
Page 6
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
2.3.2
This ‘willingness to pay’ will vary considerably, depending on such factors as the income of
the individual traveller, the value of the journey purpose and its urgency, and the comfort
and attractiveness of the journey itself. Different values may therefore correctly be
attributed to:
 time spent on the same activity by different people, whose incomes and journey
characteristics may vary; and
 time spent by the same individual on different journeys or parts of journeys.
2.3.3
One important specific application of this second type of variability is that time spent
walking to/from and waiting for public transport services is commonly valued much more
highly than time spent actually travelling. There is consistent evidence that people will pay
more to save walking and waiting time than they will for an equivalent saving in ride time.
This approach should normally be adopted for multi-modal transport appraisal.
2.3.4
Time savings to travellers in their own time typically make up a large proportion of the
benefits of transport investment. If values of time for appraisal are based on an individual’s
willingness to pay (behavioural values) which are related to income, then strategies and
plans will be biased towards those measures which most benefit travellers with higher
incomes (which may favour some modes over others). Investment will then be
concentrated into high-income areas, and the interests of those on lower incomes, who
may already suffer from relatively lower mobility and accessibility, will be given less weight.
For this reason, multi-modal transport appraisal should normally adopt the values for nonworking time which is common across all modes and journey purposes.
Recommended values
2.3.5
The values for non-working time apply to all non-work journey purposes, including travel to
and from work, by all modes. It is based on research conducted by the Institute for
Transport Studies (ITS) for the Department for Transport, reported in 2003, and published
as Values of Travel Time Saving in the UK. The values have since been re-based with
2008-2010 National Travel Survey data and converted to 2010 values and prices by
uplifting tor reflect growth in the values with income (with a GDP/capita elasticity of 1) and
changes in prices (using the GDP deflator).
2.3.6
‘Commuting’ is travelling to and from the normal place of work. ‘Other’ is travel for other
non-work purposes, for example leisure trips. There is no differentiation of ‘commuting’ and
‘other’ values of time by mode 3 .
2.3.7
The recommended values for all non-working trips are shown in Table 2. The values given
in this table are averages which include retired persons in the calculations.
2.3.8
Individual consumers perceive costs in the market price unit of account and therefore the
perceived cost and the market price are the same for ‘commuting’ and ‘other’ purposes.
2.3.9
The values for non-working time (‘commuting’ and ‘other’) spent waiting for public transport
is two and a half times the ‘commuting’ and ‘other’ values.
2.3.10 Where walking and cycling is used as a means of access to, or inter-change between
modes of transport, the non-working values (‘commuting’ and ‘other’) of walking and
cycling is twice the ‘commuting’ and ‘other’ values.
3
Based on research conducted by the Institute for Transport Studies (ITS) for the Department for
Transport, reported in 2003, and published as Values of Travel Time Saving in the UK.
Page 7
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 2 Values of Non- Working Time per person (£ per hour,
2010 prices and values)
Purpose
Commuting
Other
Resource
Cost
5.72
5.08
Perceived
Cost
6.81
6.04
Market
Price
6.81
6.04
Sensitivity tests
2.3.11 Further research by ITS Leeds, Advice on Statistical Confidence of Appraisal NonWork Values of Time, 2012, estimated the statistical confidence intervals around the
values for ‘commuting’ and ‘other’. The confidence intervals widen over time due to the
impact of GDP growth. Analysis of applying the lower and upper confidence interval values
to a wide range of schemes showed that the impact is approximately +/-25% of the present
value of non-work time savings.
2.3.12 As with the values of working time, this range should be applied in sensitivity testing. This
analysis should be carried out and reported separately from analysis carried out on values
of working time.
2.4
Annual Rates of Growth in Values of Travel Time Savings
Forecast Growth in Real GDP, Population and Households
2.4.1
Table 3a contains forecasts of annual real GDP growth per head and real GDP growth per
household. These are for use in appraisal across all valuations in WebTAG that are
assumed to grow in line with income. Figures in Table 3a and Table 3b are percentage
changes on a year earlier.
2.4.2
Important note for those using these values in modelling: In 2012, HM Treasury
altered its GDP deflator to be based on the Consumer Prices index (CPI) rather than the
Retail Prices Index (RPI) as used in the previous version of this Unit. Analysts using
longitudinal models, based on time series and calibrated using the values given in earlier
versions of this Unit, may need to recalibrate their models before using these values.
Models validated using cross-sectional data for a single year should not be affected by this
and can continue to use these new values in their models as normal.
Page 8
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 3 a Forecast Growth in Real GDP, Population and Households
Year
GDP
Growth
(%pa)
Population
Growth
(%pa)
Household
Growth
(%pa)
GDP
Growth
per head
% pa)
GDP
Growth
per
household
(% pa)
2003
3.95
0.39
0.41
3.54
3.52
2004
3.17
0.49
0.23
2.67
2.93
2005
3.23
0.66
0.78
2.56
2.44
2006
2.76
0.58
0.53
2.16
2.21
2007
3.43
0.66
0.77
2.75
2.64
2008
-0.77
0.68
0.90
-1.44
-1.66
2009
-5.17
0.64
0.56
-5.77
-5.70
2010
1.66
0.76
0.68
0.89
0.97
2011
1.12
0.71
0.50
0.40
0.62
2012
0.17
0.71
0.84
-0.54
-0.67
2013
0.60
0.71
1.00
-0.11
-0.40
2014
1.80
0.70
1.07
1.09
0.72
2015
2.30
0.68
1.06
1.61
1.23
2016
2.70
0.66
1.05
2.03
1.63
2017
2.80
0.63
1.03
2.15
1.75
2018
2.80
0.62
1.02
2.17
1.76
2019
2.80
0.60
0.98
2.18
1.80
2020
2.80
0.59
0.97
2.20
1.81
2021
2.40
0.58
0.96
1.81
1.43
2022
2.40
0.56
0.95
1.83
1.44
2023
2.40
0.54
0.94
1.85
1.45
2024
2.40
0.53
0.88
1.87
1.51
2025
2.50
0.51
0.87
1.98
1.62
2026
2.50
0.49
0.87
2.00
1.62
2027
2.50
0.47
0.86
2.02
1.63
2028
2.50
0.45
0.85
2.04
1.64
2029
2.50
0.44
0.78
2.05
1.71
2030
2.50
0.42
0.77
2.07
1.72
2031
2.40
0.41
0.77
1.98
1.62
2032
2.40
0.40
0.76
1.99
1.63
2033
2.40
0.39
0.75
2.00
1.64
2034
2.30
0.38
0.38
1.91
1.91
2035
2.40
0.38
0.38
2.02
2.02
2036
2.40
0.37
0.37
2.02
2.02
2037
2.40
0.36
0.36
2.03
2.03
2038
2.40
0.36
0.36
2.03
2.03
2039
2.40
0.36
0.36
2.03
2.03
Page 9
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Year
GDP
Growth
(%pa)
Population
Growth
(%pa)
Household
Growth
(%pa)
GDP
Growth
per head
% pa)
GDP
Growth
per
household
(% pa)
2040
2.50
0.36
0.36
2.13
2.13
2041
2.50
0.36
0.36
2.13
2.13
2042
2.50
0.35
0.35
2.14
2.14
2043
2.50
0.35
0.35
2.14
2.14
2044
2.50
0.35
0.35
2.14
2.14
2045
2.50
0.35
0.35
2.14
2.14
2046
2.50
0.35
0.35
2.14
2.14
2047
2.40
0.32
0.32
2.07
2.07
2048
2.40
0.32
0.32
2.07
2.07
2049
2.40
0.32
0.32
2.07
2.07
2050
2.40
0.32
0.32
2.07
2.07
2051
2.40
0.32
0.32
2.07
2.07
2052
2.30
0.28
0.28
2.02
2.02
2053
2.30
0.28
0.28
2.02
2.02
2054
2.30
0.28
0.28
2.02
2.02
2055
2.30
0.28
0.28
2.02
2.02
2056
2.30
0.25
0.25
2.04
2.04
2057
2.30
0.25
0.25
2.04
2.04
2058
2.30
0.25
0.25
2.04
2.04
2059
2.30
0.25
0.25
2.04
2.04
2060
2061
onward
2.40
0.25
0.25
2.14
2.14
2.40
0.25
0.25
2.15
2.15
Notes:
1. Real GDP growth per head between 2002 and 2010 is based on GDP per head growth as measured by the
ONS, Table IHXW, August 2013.
2. Real GDP growth for 2011 and 2012 is based on ONS series ABMI, August 2013. For years from 2013 to 2017
real GDP growth is based on Office of Budget Responsibility Budget 2013 forecasts
3. Real GDP growth from 2017 onwards is based on long term Office of Budget Responsibility central projections
as published in the July 2013 Fiscal Sustainability Report.
4. Population growth from 2011 onwards is based on GAD/ONS low migration projections for the United Kingdom,
projection baseline year 2010 for 2011-2016 and baseline 2008 for years 2017 onwards. The value for 2061
onward is based on the annual average growth between 2060 and 2083.
5. Household growth values presented are based on 2008 household growth projections made by CLG. Beyond
2033, household growth has been extrapolated to grow in line with population growth, holding household size
constant.
Annual Rates of Growth in Values of Travel Time Savings
2.4.3
The value of non-working time is assumed to increase with income, with an elasticity 4 of
1.0, based on the in-vehicle time elasticity estimated by Abrantes and Wardman (2010).
Working values of time are assumed to grow in line with income, with an elasticity of 1.0.
4
Elasticity is the relative response of one variable to changes in another variable. The phrase
"relative response" is best interpreted as the percentage change. In this context, the inter-temporal
income elasticity of the value of time, is the percentage change in the value of time (over time)
measured against the percentage change in income (over time).
Page 10
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
The measure of income used is GDP per head (see Table 3a). Forecast growth in the real
value of time is shown in Table 3b.
Table 3b: Forecast Growth in the Working and Non-Working Values of Time
2.5
Year
Work VOT
Growth
(% pa)
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
3.54
2.67
2.56
2.16
2.75
-1.44
-5.77
0.89
0.40
-0.54
-0.11
1.09
1.61
2.03
2.15
2.17
2.18
2.20
1.81
1.83
1.85
1.87
1.98
2.00
2.02
2.04
2.05
2.07
1.98
Non-Work
VOT
Growth
(% pa)
3.54
2.67
2.56
2.16
2.75
-1.44
-5.77
0.89
0.40
-0.54
-0.11
1.09
1.61
2.03
2.15
2.17
2.18
2.20
1.81
1.83
1.85
1.87
1.98
2.00
2.02
2.04
2.05
2.07
1.98
Year
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
onward
1.99
2.00
1.91
2.02
2.02
2.03
2.03
2.03
2.13
2.13
2.14
2.14
2.14
2.14
2.14
2.07
2.07
2.07
2.07
2.07
2.02
2.02
2.02
2.02
2.04
2.04
2.04
2.04
2.14
Non-Work
VOT
Growth
(% pa)
1.99
2.00
1.91
2.02
2.02
2.03
2.03
2.03
2.13
2.13
2.14
2.14
2.14
2.14
2.14
2.07
2.07
2.07
2.07
2.07
2.02
2.02
2.02
2.02
2.04
2.04
2.04
2.04
2.14
2.15
2.15
Work VOT
Growth
(% pa)
Values of Travel Time Savings per Vehicle
Vehicle Occupancies
2.5.1
Car occupancy figures are shown in Table 4. These figures were derived from the 1999 2001 National Travel Survey and show the sum of driver occupancy (always 1) and
passenger occupancy. Occupancies in the top half of Table 4 are expressed in per vehicle
kilometre and those in the bottom half are per trip.
Page 11
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 4 Car Occupancies (2000)
Journey
Purpose
Weekday
7am –
10am
10am – 4pm –
4pm
7pm
7pm –
7am
Weekend All Week
Weekday Average Average
Average
Occupancy Per Vehicle Kilometre Travelled
Work
Commuting
Other
Average Car
1.23
1.16
1.71
1.37
1.19
1.15
1.78
1.59
1.17
1.13
1.82
1.45
1.18
1.13
1.77
1.47
1.20
1.14
1.78
1.48
1.28
1.14
1.97
1.88
1.20
1.14
1.85
1.58
1.21
1.13
1.71
1.54
1.21
1.15
1.72
1.54
1.30
1.13
1.96
1.88
1.22
1.14
1.79
1.63
Occupancy Per Trip
Work
Commuting
Other
Average Car
2.5.2
1.26
1.16
1.72
1.46
1.19
1.14
1.70
1.59
1.20
1.14
1.76
1.53
Occupancies for all other vehicles are shown in Table 5. These figures also show the sum
of driver and passenger occupancy. Occupancies for different times of the day are only
available for cars. For LGVs, different occupancy figures are available for a weekday and
the weekend. For all other vehicles, only all week average occupancy figures are available.
These should be used for all time periods. Values for heavy and light rail are not included
as it is assumed that, if a public transport project is being appraised, a project specific
public transport model will be used which will give appropriate details of passenger
occupancy. Average PSV occupancy figures are given, as these are required for highways
scheme appraisal.
Table 5 Vehicle Occupancies (2000)
Vehicle Type and Journey
Purpose
Occupancy per Vehicle Kilometre
Travelled
Weekday
Average
Weekend
Average
All Week
Average
LGV
Work (freight)
Non Work (commuting and other)
Average LGV
1.20
1.46
1.23
1.26
2.03
1.35
1.20
1.59
1.25
OGV1 Work only
OGV2 Work only
1.00
1.00
1.00
1.00
1.00
1.00
PSV
Driver
Passenger
1.00
12.20
1.00
12.20
1.00
12.20
Page 12
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
2.5.3
Table 6 shows the predicted decline in car passenger occupancies as an annual
percentage until 2036, after which car passengers are assumed to remain constant. The
occupancy of all other vehicle types should be assumed to remain unchanged over time.
Table 6 Annual Percentage Change in Car Passenger Occupancy (% pa) up to 2036
Journey
Purpose
Work
Non – Work
(commuting
and other)
Weekday
7am –
10am
-0.48
10am –
4pm
-0.4
4pm –
7pm
-0.62
7pm –
7am
-0.5
Weekday
Average
-0.44
Weekend All Week
-0.48
-0.45
-0.67
-0.65
-0.53
-0.47
-0.59
-0.52
-0.56
Journey Purpose Splits
2.5.4
Data from the National Travel Survey (1999 – 2001) has been used to produce journey
purpose splits for work and non-work travel (commuting and other), based on distance
travelled and trips made. These purpose splits are necessary in order to calculate values of
time per vehicle for the average vehicle. Journey purpose splits are assumed to remain
constant over time.
2.5.5
The purpose splits based on distance travelled in work and non-work time are given in
Table 7.
Page 13
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 7 Proportion of Travel in Work and Non-Work Time
Mode /Vehicle
Type
& Journey
Purpose
Weekday
7am – 10am 4pm – 7pm – Weekday
10am – 4pm 7pm 7am
Average
Weekend All Week
Average Average
Percentage of Distance Travelled by Vehicles
Car
Work
Commuting
Other
18.1
46.0
35.9
19.9
11.4
68.7
13.0
40.8
46.2
12.3
36.2
51.5
16.4
31.0
52.5
3.2
8.5
88.3
13.1
25.3
61.6
88.0
88.0
88.0
88.0
88.0
88.0
88.0
12.0
12.0
12.0
12.0
12.0
12.0
12.0
OGV1
Work
100
100
100
100
100
100
100
OGV2
Work
100
100
100
100
100
100
100
LGV
Work
(freight)
Non – Work
(Commuting
and Other)
Percentage of Distance Travelled by Occupants
Car
Work
Commuting
Other
15.4
38.3
46.4
13.8
8.1
78.1
10.2
32.2
57.6
9.9
29.1
61.0
12.6
23.9
63.5
2.0
5.1
92.9
9.2
18.0
72.7
PSV
Work
Commuting
Other
3.9
30.0
66.1
2.0
11.1
86.9
3.9
36.6
59.5
5.7
38.1
56.2
3.4
25.5
71.1
1.5
6.4
92.0
2.9
20.5
76.6
Heavy Rail
Work
Commuting
Other
14.1
51.9
34.1
22.4
10.2
67.4
16.4
55.9
27.7
23.2
53.1
23.7
18.3
43.7
38.1
6.3
4.3
89.5
16.5
37.8
45.7
Light Rail
Work
Commuting
Other
1.9
82.4
15.7
0.2
8.5
91.3
1.8
75.7
22.5
2.3
28.9
68.9
1.3
50.1
48.6
0.4
23.3
76.3
1.2
45.8
53.1
Note: The shaded areas in the table indicate a small sample, hence these figures should
be treated with caution.
2.5.6
The purpose splits based on trips made in work and non-work time are given in Table 8.
Page 14
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 8 Proportion of Trips Made in Work and Non-Work Time
Mode /Vehicle
Type and
Journey
Purpose
Weekday
Weekend All Week
7am – 10am – 4pm – 7pm – Weekday Average Average
10am 4pm
7pm
7am
Average
Percentage of Vehicle Trips
Car
Work
Commuting
Other
6.8
40.6
52.7
8.3
11.6
80.1
5.5
32.3
62.2
3.6
26.4
70.0
6.5
25.4
68.1
1.7
9.1
89.3
5.0
20.3
74.7
88.0
88.0
88.0
88.0
88.0
88.0
88.0
12.0
12.0
12.0
12.0
12.0
12.0
12.0
OGV1
Work
100
100
100
100
100
100
100
OGV2
Work
100
100
100
100
100
100
100
LGV
Work(freight)
Non-Work
(Commuting and
Other)
Percentage of Person Trips
Car
Work
Commuting
Other
5.2
33.3
61.5
2.2
15.6
82.2
4.1
25.8
70.1
1.2
10.9
87.9
4.7
20.0
75.3
1.1
6.4
92.5
3.4
15.2
81.4
PSV
Work
Commuting
Other
1.5
41.7
56.8
1.2
10.6
88.2
1.8
43.0
55.2
2.6
47.4
50.0
1.5
26.9
71.5
1.0
12.4
86.6
1.4
24.3
74.3
Heavy Rail
Work
Commuting
Other
6.7
71.7
21.6
13.6
14.9
71.5
6.7
68.0
25.4
8.8
60.4
30.8
8.3
58.2
33.5
2.8
11.1
86.1
7.6
52.2
40.3
Light Rail
Work
Commuting
Other
2.8
83.0
14.2
0.7
10.8
88.5
3.3
70.7
26.0
5.3
23.7
71.1
2.4
48.2
49.4
1.2
21.7
77.1
2.2
43.8
54.0
Note: The shaded areas in the table indicate a small sample, hence these figures should
be treated with caution.
Values of Time per Vehicle
2.5.7
The market price values of time per vehicle are given in Table 9. These values were
calculated by multiplication of the appropriate figures from Tables 1, 2, 4, 5 and 6. Average
Page 15
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
car, average LGV and average PSV values also use the journey purpose split data from
Table 7 as weights. The values are based on distance travelled.
Table 9 Market Price Values of Time per Vehicle based on distance travelled (£
per hour, 2010 prices and values)
Vehicle Type Weekday
and Journey
7am – 10am – 4pm –
Purpose
10am
4pm
7pm
Car
Work
Commuting
Other
Average Car
LGV
Work
(freight)
Non – Work
(Commuting
and Other)
Average
LGV
OGV
OGV1
Working
OGV2
Working
PSV
(Occupants)
Work
Commuting
Other
Total
2.5.8
7pm –
7am
Average
Weekday
Weekend All Week
31.56
7.83
10.06
12.92
30.81
7.77
10.46
14.20
30.34
7.65
10.74
12.03
30.58
7.66
10.48
11.93
30.99
7.71
10.49
12.98
32.54
7.72
11.61
11.95
30.99
7.71
10.90
12.73
14.62
14.62
14.62
14.62
14.62
15.35
14.62
9.15
9.15
9.15
9.15
9.15
12.72
9.97
13.96
13.96
13.96
13.96
13.96
15.03
14.06
14.35
14.35
14.35
14.35
14.35
14.35
14.35
14.35
14.35
14.35
14.35
14.35
14.35
14.35
22.57
24.93
48.74
96.24
18.72
9.22
64.08
92.02
22.57
30.41
43.88
96.86
26.22
31.66
41.44
99.32
21.56
21.19
52.43
95.18
17.70
5.32
67.84
90.86
20.54
17.03
56.49
94.06
Using the values in Table 9 above together with the national average vehicle proportions
for 2002 taken from the COBA user manual, Table 8/1, the market price value of time for
an average vehicle is £13.87 per hour, 2010 prices and values.
Page 16
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
3
Vehicle Operating Costs
3.1.1
The use of the road system by private cars and lorries gives rise to operating costs for the
user. These include the obvious costs of fuel (or, for modern plug-in electric vehicles,
mains electricity), oil and tyres, and an element of vehicle maintenance. The models for car
and goods vehicle operating costs also include allowances for the purchase of new
vehicles, as discussed below.
3.1.2
The distance-related costs to private households and business of car purchase are
included in the car non-fuel operating costs by inclusion of an allowance for mileage related
depreciation. In addition, for business cars, an allowance is also made for the decline in
vehicle capital value (other than that accounted for by mileage related depreciation).
3.1.3
The costs to freight carriers of goods vehicle purchases are taken into account under
goods vehicle non-fuel operating costs. As with private cars, it is assumed that the decision
to purchase goods vehicles is independent of the transport policy option pursued.
However, changes in congestion on the road system will influence the productivity with
which any given fleet of goods vehicles can be used, and this element is taken into account
in computing goods vehicle operating costs.
3.1.4
This section provides the latest vehicle operating cost (VOC) values recommended by the
Department for use in economic appraisals of transport projects. VOCs are separated into
fuel VOCs and non-fuel VOCs and are discussed separately within this section.
3.1.5
Values for cars and LGVs are split by energy source (whether petrol or diesel, fuel, or, at
present in the case of cars only, mains electricity). The split is by energy source, not
vehicle type – vehicle kilometres for a plug-in hybrid vehicle are split according to the
energy source used. Some values are given for an average car or average LGV, but
analysts are advised that these can give slightly different results, so it is preferable to use
the separate values by fuel type.
3.1.6
The appraisal of electric cars is a developing area. It should be noted that, whilst VOCs for
electric cars are considered in this unit, some of the other environmental impacts of electric
cars, such as noise and air quality, are not considered at present.
3.1.7
Assumptions on the share of vehicle kilometres by energy source over time and projections
of vehicle fuel efficiency take into account the impact of announced and committed
policies only. For example, the car fuel efficiency projection reflects EU CO2 regulation
which sets targets for average new car emissions in 2015 and 2020. As the policy has only
been agreed up to 2020, the projection does not make assumptions about future, lower
post-2020 target levels. Instead it assumes that the 2020 target level holds for all
subsequent years. When further policy measures in this area are agreed the guidance will
be updated to incorporate them.
3.1.8
Following the change in the Department’s model base year, values in this section are
based on 2010 values and prices. However, some historic values are provided (back to
2006) to support recent historic models.
3.2
Vehicle Operating Costs – Fuel and Electricity
3.2.1
Fuel consumption is estimated using a function of the form:
L = a/v + b + c.v + d.v2
Where:
L = consumption, expressed in litres per kilometre;
Page 17
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
v = average speed in kilometres per hour; and
a, b, c, d are parameters defined for each vehicle category.
3.2.2
The revised fuel consumption aggregated equation for WebTAG vehicle groups was
derived 5 using the results from the New UK Road Vehicle Emission Factors Database that
relates the rate of emission of a pollutant or fuel consumption to average vehicle speed.
The results of the Database consultation, documents and spreadsheets can be found at:
http://www.dft.gov.uk/pgr/roads/environment/emissions/ This function improves the
relationship between speed and fuel consumption especially at low speeds (down to 5
kph). Figure 2 and Figure 3 show how fuel consumption varies with speed, using these
functions. Similar graphs can be obtained at the link above by downloading the two
spreadsheets Road vehicle emission factors 2009 – regulated and Viewer –
Road vehicle emission factors 2009 and opening the second of these spreadsheets.
3.2.3
Evidence of the energy consumption of electric cars is currently limited. At present, it
should be assumed that energy consumption is proportional to distance but independent of
speed (ie, equivalent to a “b” parameter in the fuel consumption formula with the a, c and d
parameters all zero). The appraisal of electric cars is a developing area and we expect to
develop speed-related curves in the future. Electric cars should only be included in
models/appraisals from 2011 onwards.
30
25
Litres/100km
20
Overall Cars
Overall LGVs
15
10
5
0
0
20
40
60
80
100
120
140
160
Speed kph
Figure 2 Fuel consumption rates at different speeds – Cars and LGVs
5
TRL unpublished report “Fuel Consumption Equations” dated 29 September 2008.
Page 18
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
120
110
100
90
Litres/100km
80
70
Overall OGV
PSVs
60
50
40
30
20
10
0
0
20
40
60
80
100
120
140
160
Speed kph
Figure 3 Fuel consumption rates at different speeds – OGVs and PSVs
3.2.4
The parameters needed to calculate the fuel/energy consumption element of VOCs are
given in Table 10. The fuel consumption parameter values are based on a 2010 vehicle
fleet (updated from the 2002 values in previous versions), whilst the electrical energy
consumption values are based on 2011 values.
Table 10: Fuel/Energy Consumption Formulae Parameter Values
Parameters
Vehicle
Category
a
b
c
d
Fuel Consumption Parameter Values (litres per km, 2010)
Petrol Car
Diesel Car
Petrol LGV
Diesel LGV
OGV1
OGV2
PSV
0.964022581
0.437094041
1.556463336
1.045268333
1.477368474
3.390702946
4.115603124
0.041448033
0.058616489
0.064253318
0.057901415
0.245615208
0.394379054
0.306464813
-4.54163E-05
-0.00052488
-0.000744481
-0.000432895
-0.003572413
-0.004642285
-0.00420643
2.01346E-06
4.12709E-06
1.00552E-05
8.0252E-06
3.0638E-05
3.59224E-05
3.65263E-05
Energy Consumption Parameter Values (kWh per km, 2011)
Electric Car
3.2.5
0.12564236
In Table 10a and Table 10b the VOC parameters have been converted into pence per
kilometre by multiplying by the cost of fuel, calculated from Table 11. OGV1, OGV2 and
PSV are assumed to be diesel driven and therefore parameters for these vehicles have
been multiplied by the resource cost of diesel. The parameters for average car and
average LGV are calculated as the average across different fuel/energy types. In the
Page 19
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
absence of more specific evidence it has been assumed that the proportions of traffic by
fuel type are broadly equivalent to the proportions of vehicle kilometres by fuel type as
shown in Table 12.
3.2.6
Table 10 no longer provides consumption values for an “average car”, as units for electric
cars (kWh) differ from the units for petrol and diesel cars (litres). However, it is possible to
convert the consumption values into costs (using the costs per unit given in Table 11a and
Table 11b) and estimate the fuel/energy cost per kilometre for an average car. Examples of
this are given in Table 10a (which gives 2010 values, excluding electric cars) and Table
10b (which gives 2011 values, including electric cars and a combined average for petrol,
diesel and electric cars). Values for an average car are weighted using the petrol, diesel
and electric car proportions given in Table 12. For more details about how the cost per
kilometre by year changes, please see Table 14.
Table 10a: Fuel/Energy Cost Formulae Parameter Values (2010 values and prices)
Parameters
Vehicle
Category
a
b
Values excluding VAT (for vehicles in course of work)
c
Petrol Car
Diesel Car
Average Car
Petrol LGV
Diesel LGV
Average LGV
OGV1 (diesel)
OGV2 (diesel)
PSV (diesel)
d
96.167
4.135
-0.00453
44.364
5.949
-0.05327
75.068
4.874
-0.02438
155.266
6.410
-0.07427
106.091
5.877
-0.04394
108.974
5.908
-0.04572
149.948
24.929
-0.36259
344.145
40.028
-0.47118
417.720
31.105
-0.42694
Values including VAT (for vehicles in course of other purposes)
0.00020
0.00042
0.00029
0.00100
0.00081
0.00083
0.00311
0.00365
0.00371
Petrol Car
Diesel Car
Average Car
Petrol LGV
Diesel LGV
Average LGV
0.00024
0.00049
0.00034
0.00118
0.00096
0.00097
112.996
52.127
88.205
182.438
124.657
128.044
4.858
6.991
5.727
7.531
6.905
6.942
-0.00532
-0.06260
-0.02865
-0.08726
-0.05163
-0.05372
Note: In 2010 it is assumed there are no electric cars, so the “Average Car” is an average
over petrol and diesel.
Page 20
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 10b: Fuel/Energy Cost Formulae Parameter Values (2011 values, 2010 prices)
Parameters
Vehicle
Category
a
b
Values excluding VAT (for vehicles in course of work)
Petrol Car
Diesel Car
Electric Car
Average Car
Petrol LGV
Diesel LGV
Average LGV
OGV1 (diesel)
OGV2 (diesel)
PSV (diesel)
102.650
48.525
Petrol Car
Diesel Car
Electric Car
Average Car
Petrol LGV
Diesel LGV
Average LGV
123.180
58.230
c
4.413
-0.00484
6.507
-0.05827
1.621
79.367
5.312
-0.02779
168.155
6.942
-0.08043
115.619
6.405
-0.04788
118.465
6.434
-0.04965
166.868
27.742
-0.40350
382.979
44.545
-0.52434
464.856
34.615
-0.47511
Values including VAT (for vehicles in course of other purposes)
95.240
201.785
138.743
142.158
5.296
7.809
1.702
6.374
8.330
7.685
7.720
d
0.00021
0.00046
0.00032
0.00109
0.00089
0.00090
0.00346
0.00406
0.00413
-0.006
-0.070
0.000
0.001
-0.033
-0.097
-0.057
-0.060
0.000
0.001
0.001
0.001
3.2.7
DfT has developed recommended energy consumption rates by stock type for use in
appraisal of rail schemes, which can be accessed by contacting the Department. Should
practitioners decide to use alternative energy consumption rates, the supporting written
documentation should report the rates adopted and make clear the business case impact
of not using DfT’s recommended rates.
3.2.8
Standard assumptions for fuel and electricity prices are shown in Table 11a, including
forecasts to 2030. Historic values are provided back to 2002, as these may be useful for
the purpose of transport modelling.
3.2.9
Petrol, diesel and gas oil prices are annual average values. Values up to 2012 are
observed, whereas values from 2013 onwards are forecasts based on the central scenario
published in October 2012 by the Department of Energy and Climate Change (DECC). In
Table 11a, ‘Petrol’ is a weighted average between Ultra Low Sulphur Petrol (standard
unleaded) and Super Unleaded. Super Unleaded is assumed to constitute 10% of the
petrol market by 2030. ‘Diesel’ comprises both Ultra Low Sulphur and Sulphur Free
varieties. The ‘Gas Oil’ series is based on the DECC series for retail industrial oil prices.
3.2.10 The resource cost of fuel VOCs is net of indirect taxation. The market price is gross of
indirect taxation and is therefore the sum of the resource cost and fuel duty, plus VAT (that
is, market price = [resource cost + fuel duty] x [1 + VAT]). In work time the perceived cost
of fuel VOCs is the cost perceived by businesses. Businesses are generally viewed as
perceiving costs in the factor cost unit of account as most business costs are free of
indirect taxation because they can claim it back. However, businesses cannot reclaim fuel
duty and therefore the perceived value of fuel VOCs in work time is equal to the resource
cost plus fuel duty. In non-work time, the perceived cost of fuel VOCs is the cost as
Page 21
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
perceived by the individual consumer. Consumers perceive costs in the market prices unit
of account and therefore the perceived value of fuel VOCs in non-working time is equal to
the market price.
3.2.11 Values for fuel duty and VAT in Table 11a take account of all changes announced in the
2013 Budget Report (HMT March 2013), including the decision to cancel the increase in
fuel duty planned for September 2013. Fuel duty is assumed to increase in line with RPI on
1 April in all subsequent years.
3.2.12 Electricity resource prices are for domestic electricity based on tables produced by the
Interdepartmental Analysis Group (IAG) at DECC, October 2012. As well as the wholesale
cost of producing the electricity, these resource costs include the supplier margin and
impact of policies. The only indirect tax relating to electricity is VAT, at a rate of 5%. VAT
should not be applied for business users, including all rail operators, as they can claim it
back.
3.2.13 The actual price of a unit of electricity may vary according to the type of electricity used
(domestic, commercial or industrial) which in itself will depend on where electric cars are
recharged. We would expect much of the electricity for electric cars to be charged at the
domestic rate. At the same time, the rail industry pays a much lower price for electricity
than domestic users. Therefore, it is assumed that:
 for cars, the electricity price will be the DECC IAG domestic retail price to 2030;
 for rail, the electricity price will be the DECC IAG industrial retail price to 2030.
3.2.14 Beyond 2030, the resource cost of electricity for both car and rail (which may be expected
to include the damage cost of the carbon emissions that they generate) is assumed to vary
according to the changing cost of carbon emissions for generating 1 kWh of electricity.
These values are shown in Table 11b.
3.2.15 The values in Table 11a have been deflated to 2010 prices using HM Treasury’s GDP
deflator. The GDP deflator is a much broader price index than the CPI, RPI or RPIX (which
only measure consumer prices) as it reflects the prices of all domestically produced goods
and services in the economy. Hence, the GDP deflator also includes the prices of
investment goods, government services and exports, and subtracts the price of UK
imports. The wider coverage of the GDP deflator makes it more appropriate for deflating
public expenditure series. We therefore recommend the GDP deflator is used to deflate
value for appraisals.
3.2.16 For petrol, diesel and gas oil beyond 2030, the resource costs are assumed to remain
constant in real terms but duty prices are forecast to grow at a real rate of 1.17% per year.
This is because fuel duty is assumed to grow in line with RPI inflation, which is forecast to
exceed GDP deflator growth by 1.2% in the long-run 6 .
6
http://cdn.budgetresponsibility.independent.gov.uk/Working-paper-No2-The-long-run-differencebetween-RPI-and-CPI-inflation.pdf
Page 22
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 11a Fuel and Electricity Prices and Components (2010 prices)
Year
2002*
2003*
2004*
2005*
2006*
2007*
2008*
2009*
2010*
2011*
2012*
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
Resource Cost
Duty
Petrol
Diesel
Gas
Oil
(p/litre)
(p/litre)
(p/litre)
20.29 22.34
16.67
22.26 23.91
18.28
24.70 26.13
20.15
30.49 34.11
25.51
33.72 37.09
29.98
33.91 36.02
28.29
42.64 51.53
43.49
33.13 36.97
32.59
42.57 44.31
40.49
51.89 56.08
51.50
53.07 58.04
52.70
53.17 59.27
53.15
53.61 59.75
53.64
54.02 60.19
54.09
54.46 60.67
54.58
54.87 61.11
55.03
55.31 61.59
55.52
55.76 62.08
56.02
56.20 62.56
56.51
56.65 63.04
57.00
57.09 63.52
57.49
57.54 64.01
57.99
58.02 64.53
58.53
58.47 65.02
59.02
58.95 65.54
59.56
59.39 66.03
60.05
59.88 66.55
60.59
60.36 67.08
61.12
60.84 67.61
61.66
* actual prices / rates
Electricity
VAT rate
Petrol
Diesel
Gas
Oil
Electric
Petrol
Diesel
(p/kWh)
(%)
(%)
(%)
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
17.5
17.5
17.5
17.5
17.5
17.5
17.3
15
17.5
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
17.5
17.5
17.5
17.5
17.5
17.5
17.3
15
17.5
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
Road
Rail
(p/kWh)
(p/kWh)
(p/litre)
(p/litre)
(p/litre)
6.87
7.10
7.34
8.34
9.44
9.96
10.63
10.98
11.15
11.39
11.60
11.85
12.30
12.39
12.67
12.93
12.95
12.87
13.19
13.27
12.88
55.64
54.69
54.42
53.15
51.76
52.41
52.60
55.90
57.19
56.87
55.83
54.68
54.11
54.86
55.83
57.03
58.14
59.15
60.04
60.82
61.47
62.13
62.86
63.60
64.35
65.10
65.87
66.64
67.42
55.64
54.69
54.42
53.15
51.76
52.41
52.60
55.90
57.19
56.87
55.83
54.68
54.11
54.86
55.83
57.03
58.14
59.15
60.04
60.82
61.47
62.13
62.86
63.60
64.35
65.10
65.87
66.64
67.42
3.85
4.63
5.04
6.08
7.27
8.90
10.04
10.67
10.92
10.82
10.52
10.98
10.99
11.11
11.27
11.42
11.55
11.68
11.79
11.90
12.00
12.11
12.21
12.32
12.43
12.54
12.65
12.76
12.87
12.34
12.90
13.59
13.96
15.26
16.67
17.15
18.13
18.29
18.16
18.46
18.43
18.77
18.38
18.57
19.04
19.13
18.75
19.30
19.44
18.98
Electric
Road
Page 23
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 11b Resource cost of electricity from 2031 (2010 prices)
Year
Road
(p/kWh)
Rail
(p/kWh)
Year
Road
(p/kWh)
Rail
(p/kWh)
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
19.00
19.02
19.02
19.03
19.02
19.02
19.01
19.00
18.99
18.98
18.91
18.97
18.87
18.77
18.76
18.79
18.79
18.87
18.83
18.75
18.77
18.79
18.81
18.83
18.84
18.86
18.88
18.89
18.91
18.93
18.94
18.95
18.96
18.97
18.98
12.90
12.91
12.92
12.92
12.92
12.92
12.91
12.90
12.89
12.88
12.82
12.87
12.78
12.68
12.68
12.70
12.70
12.78
12.74
12.67
12.69
12.70
12.72
12.74
12.75
12.77
12.79
12.80
12.82
12.83
12.84
12.85
12.86
12.87
12.88
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
18.99
19.00
19.01
19.01
19.02
19.02
19.03
19.03
19.03
19.03
19.03
19.03
19.03
19.03
19.03
19.03
19.03
19.02
19.02
19.02
19.02
19.01
19.01
19.00
18.99
18.99
18.99
18.98
18.97
18.97
18.96
18.95
18.95
18.94
18.93
12.89
12.90
12.90
12.91
12.91
12.92
12.92
12.93
12.93
12.93
12.93
12.93
12.93
12.93
12.93
12.93
12.92
12.92
12.92
12.92
12.91
12.91
12.90
12.90
12.89
12.89
12.89
12.88
12.87
12.87
12.86
12.86
12.85
12.84
12.84
3.2.17 Table 12 provides forecasts of vehicle-kilometre proportions for diesel and petrol vehicles,
based on DfT 2010 fleet models for both cars and LGVs 7 . These forecasts are used in the
TUBA program when subdividing the total number of cars and LGVs into petrol, diesel or
electric. Values for years between 2005 and 2029 that are not shown in the table should be
estimated using linear interpolation between the two closest years. Values for 2031
onwards should be assumed to be held at 2030 levels.
7
The DfT fleet models are also used to update the NAEI assumptions that were used previously. At the
time of writing the NAEI assumptions used in DEFRA’s fleet modelling did not include electric cars, but it
is expected that they will be included in 2013. Note that in previous versions of this Unit car fleet
proportions were used in this Table.
Page 24
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 12 Proportion of Cars and LGV Vehicle Kms Using Petrol,
Diesel or mains electricity (%)
Year
Cars
LGVs
Petrol
Diesel
Electric
Petrol
Diesel
2004
73.28%
26.72%
0.00%
11.07%
88.93%
2010
59.27%
40.73%
0.00%
5.86%
94.14%
2015
47.97%
51.87%
0.16%
3.64%
96.36%
2020
43.70%
55.33%
0.96%
1.89%
98.11%
2025
44.41%
53.05%
2.54%
1.04%
98.96%
2030
44.46%
50.23%
5.31%
0.79%
99.21%
Rates of Change in Fuel VOCs
3.2.18 There are two causes of changes in fuel VOC over time: improvements in vehicle efficiency
and changes in the cost of fuel. For cars, changes in fuel VOCs also reflect changes in the
proportion of traffic using either petrol or diesel (see Table 12).
3.2.19 Vehicle efficiency assumptions are shown in Table 13. These figures show changes in fuel
consumption and therefore negative figures indicate an improvement in vehicle efficiency.
As with the consumption values noted earlier, values for an average car are no longer
provided as petrol and diesel cars no longer have common units. Table 14 shows how the
parameters to calculate fuel/energy cost per kilometre changes through time for an
average car and an average LGV. For maximum accuracy, for years not shown in Table
10b and Table 14, analysts are advised to calculate the average car and average LGV fuel
cost from Tables 10, 11, 12 and 13, as the volatility of fuel prices is such that interpolation
may not be appropriate.
3.2.20 Note that, although Table 13 shows growth rates from 2006 onwards, the base year for the
fuel consumption parameters given in Table 10 is 2010. Analysts who need to obtain
values for earlier years for older transport models should carry out the reverse year-onyear calculation to those forecasting forward (ie for each year i between the model base
year and 2009 inclusive, divide the 2010 value by (1+gi,i+1/100), where gi,i+1 is the fuel
efficiency improvement given in Table 13 below).
Page 25
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 13 Assumed Vehicle Fuel Efficiency Improvements
Year
Change in Vehicle Efficiency (% pa)
Petrol
Diesel
Petrol
Diesel
Car
-0.42
(actual)
-1.05
(actual)
-1.78
(actual)
-1.43
(actual)
Car
-0.49
(actual)
-1.07
(actual)
-0.92
(actual)
-1.63
(actual)
LGV
LGV
OGV1
OGV2
PSV
-0.01
0.00
-1.23
-1.23
0.00
-0.01
0.00
-1.23
-1.23
0.00
-1.35
(actual)
-0.34
(actual)
-1.23
(actual)
-1.80
(actual)
-1.23
-1.23
0.00
-1.23
-1.23
0.00
20102015
-2.09
-1.71
0.11
-0.66
-2.07
0.00
0.00
0.00
20152020
-3.72
-2.22
-0.31
-1.38
-2.34
0.00
0.00
0.00
20202025
-3.63
-2.62
-0.71
-3.07
-2.19
0.00
0.00
0.00
20252030
-2.10
-2.10
-1.19
-2.95
-1.30
0.00
0.00
0.00
20302035
-0.74
-0.96
-0.26
-0.86
-0.57
0.00
0.00
0.00
20062007
200720082
2008 2009
20092010
Electric
Car
Notes:
1. Petrol and diesel car values include biofuel energy penalty.
2. DVLA new car data used up to 2008, repeated from previous version of this unit.
3. Actual values for OGVs and PSVs are repeated from the previous version of this Unit.
4. Car values for 2009 onwards are consistent with EU emission targets up to 2020. LGV values for 2009 onwards
are assumed to improve due to technology transferred from cars to LGV. Both car and LGV values are derived
using DfT 2010 fleet models. OGV and PSV values are assumed not to change.
5. Values for growth prior to 2010 are shaded, as they are provided only for the purpose of backcasting for older
models. Table 10 now gives fuel consumption formulae in 2010 values.
Page 26
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 14: Average Car/LGV Fuel/Energy Cost Formulae Parameter Values (2010
prices)
Year
Parameters
a
b
c
Average Car, excluding VAT (for travel in course of Work)
2010
75.068
4.874
-0.02438
2015
69.227
5.160
-0.03087
2020
60.772
4.850
-0.03091
2025
53.750
4.320
-0.02724
2030
49.736
3.997
-0.02443
Average LGV, excluding VAT (for travel in course of Work)
2010
108.974
5.908
-0.04572
2015
110.337
6.028
-0.04608
2020
103.683
5.700
-0.04314
2025
96.820
5.342
-0.04020
2030
94.993
5.247
-0.03941
Average Car, including VAT (for travel in course of other purposes)
2010
88.205
5.727
-0.02865
2015
83.072
6.191
-0.03704
2020
72.926
5.817
-0.03710
2025
64.500
5.175
-0.03268
2030
59.683
4.779
-0.02932
Average LGV, including VAT (for travel in course of other purposes)
2010
128.044
6.942
-0.05372
2015
132.405
7.233
-0.05529
2020
124.420
6.840
-0.05177
2025
116.184
6.410
-0.04823
2030
113.992
6.297
-0.04729
d
0.00029
0.00032
0.00031
0.00027
0.00024
0.00083
0.00084
0.00079
0.00074
0.00073
0.00034
0.00038
0.00037
0.00032
0.00029
0.00097
0.00101
0.00095
0.00089
0.00087
3.3
Vehicle Operating Costs – Non-Fuel
3.3.1
The elements making up non-fuel vehicle operating costs include oil, tyres, maintenance,
depreciation and vehicle capital saving (only for vehicles in working time). The non-fuel
elements of VOC are combined in a formula of the form:
C = a1 + b1/V
where:
C = cost in pence per kilometre travelled,
V = average link speed in kilometres per hour,
a1 is a parameter for distance related costs defined for each vehicle category,
b1 is a parameter for vehicle capital saving defined for each vehicle category (this
parameter is only relevant to working vehicles).
3.3.2
Currently parameter a1 takes the same value for petrol and diesel vehicles. For electric
vehicles, the evidence is very weak, but suggests that the costs are lower because there
Page 27
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
are fewer moving parts that are likely to wear out with mileage. There is currently no
evidence to confirm whether the a1 parameter differs by trip purpose for electric cars.
3.3.3
There is also no evidence regarding the b1 parameter for electric cars in-work. For the
present it will be assumed that the vehicle capital saving for electric cars will be the same
as for petrol/diesel cars.
3.3.4
The parameters needed to calculate the non-fuel vehicle operating resource costs are
given in Table 15. These parameters exclude indirect taxation. The parameters by fuel type
are assumed to be constant through time; however, parameters for an average car vary
through time (owing to changes in the proportion of electric vehicles) and are given in
Table 16.
Table 15 Non-Fuel Resource VOCs, 2010 (2010 prices)
Vehicle
Category
Car
Work Petrol
Work Diesel
Work Electric
Non-Work Petrol
Non-Work Diesel
Non-Work Electric
Parameter
Values
b1
pence/hr
a1
pence/km
4.966
4.966
1.157
3.846
3.846
1.157
135.946
135.946
135.946
7.213
7.213
47.113
7.213
41.458
OGV1
6.714
263.817
OGV2
13.061
508.525
PSV
30.461
694.547
LGV
Work
Non-Work
(commuting and
other)
Average LGV
3.3.5
Non-fuel VOC parameters for work and non-work cars (commuting and other) and private
LGVs have been derived in accordance with previous methods outlined in Review of
Vehicle Operating Costs in COBA (EEA Division, DoT 1990-91). Non-fuel parameters
for all other vehicles have been updated from the Transport Economics Note (DfT 2001)
by the ratio of average 1998 and 2002 Retail Price Indices.
3.3.6
The marginal resource costs of oil, tyres, mileage and maintenance related depreciation,
are assumed to be fixed costs per kilometre and appear in the ‘a1’ term. The difference
between the 'a1' term for work and non-work time non-fuel car operating costs reflects the
difference in the composition of the vehicle fleet in work and non-work time. In work time, a
large proportion of total mileage is by cars with large engine sizes and these cars have
Page 28
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
higher non-fuel VOCs. The ‘b1’ term in the non-fuel costs represents changes in the
productivity of commercial vehicles and cars in working time, all goods vehicles and PSVs.
3.3.7
The time component of depreciation is excluded since it does not vary with distance or
speed. For OGVs and PSVs depreciation is assumed to be totally time related; this is
based on evidence from trade sources which suggest that factors such as obsolescence
and condition are more important determinants of vehicle value than mileage per se. For
cars and LGVs evidence from second hand prices indicates that part of their depreciation is
related to mileage; and therefore this element is recorded as a marginal resource cost.
3.3.8
For demand modelling and the calculation of consumer surplus, costs must be expressed
in perceived cost terms. The perceived cost of non-fuel VOCs differs for work and nonwork time. In work time, the perceived cost is the cost perceived by businesses and is
therefore equal to the resource cost. In non-work time, it is assumed that travellers do not
perceive non-fuel VOCs, so the perceived cost is zero.
3.3.9
The assumption that those making non-work car trips do not perceive their non-fuel vehicle
operating costs means that estimates of consumer surplus for non-work purposes, which
are based on perceived costs, do not reflect changes in non-fuel vehicle operating costs.
3.3.10 However, changes in users' expenditure on non-fuel VOCs are included in the calculation
of user benefits for non-work purposes - see Transport User Benefit Calculation (TAG
Unit 3.5.3) for details. These calculations use non-fuel VOCs expressed in market prices.
Non-fuel VOCs in market prices for non-work purposes may be estimated from the formula
given above, using the parameters given in Table 15 plus VAT (that is, market price =
resource cost x (1+VAT)).
Rates of Change in Non-Fuel VOCs
3.3.11 Non-fuel VOCs by fuel/energy type are assumed to remain constant in real terms over the
forecast period. This assumption is made because the main elements which make up nonfuel VOCs are subject to less volatility than fuel VOCs.
3.3.12 However, non-fuel VOCs for an average car varies slightly through time, owing to the
increasing proportion of electric cars. Table 16 shows how the non-fuel VOCs for cars vary
through time. The average over Work and Non-Work purposes is based on the split of car
kilometres in Table 7. Values for years between 2011 and 2029 that are not shown in Table
16 should be obtained by linear interpolation between the two nearest years; for 2031
onwards the values should be held at 2030 levels.
3.3.13 The non-fuel costs for an Average LGV given in Table 15 are assumed not to change
through time. The costs for OGVs are also assumed not to change through time.
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TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Table 16: Non-Fuel Resource VOCs through time (2010 prices)
Year
3.4
Work Car
Non-Work Car
Average Car
a1
b1
a1
b1
a1
b1
pence/km
pence/hr
pence/km
pence/hr
pence/km
pence/hr
2010
4.966
135.946
3.846
0.000
3.993
17.809
2015
4.960
135.946
3.842
0.000
3.988
17.809
2020
4.929
135.946
3.820
0.000
3.965
17.809
2025
4.869
135.946
3.778
0.000
3.921
17.809
2030
4.764
135.946
3.703
0.000
3.842
17.809
Public Transport Operating Costs
Bus Operating Costs
3.4.1
In a simple highway appraisal, buses are treated as part of the traffic flow, and the
operating cost formulae described above are applied, using the appropriate parameter
values for PSVs. In a multi-modal study, however, different options may result not only in
faster or slower running times for existing bus services, but in the need for more or different
levels and patterns of bus service provision. In these cases, the impact of options on the
costs of bus service provision have to be considered in more detail.
3.4.2
The bus operating model requires assumptions to be input on various operational
characteristics, such as sickness rates, working days per week, holiday allowances,
employers' costs, engineering spares etc and also unit cost rates for each grade of staff,
fuel and tyres etc. Vehicle fleet requirements and costs are considered as capital
expenditure outside the model and are included in option costs. The Overall Approach:
The Steps in the Process (TAG Unit 2.1) gives an overview of how costs are covered in
the appraisal process. The Estimation and Treatment of Scheme Costs (TAG Unit
3.5.9) provides further detail on estimating and treating costs for use in the appraisal
process.
3.4.3
Bus operating costs vary by region and by service type. Information on the operating cost
of local bus services, by area, can be found in Focus on Public Transport and in The
Passenger Transport Industry in Great Britain Facts (Confederation of Passenger
Transport 1999-2000). Where no other information is available, these costs should be
used as default indicators of the operating cost of bus services. However, more detailed
information on bus costs should be sought where bus based measures are likely to play a
significant part in a strategy. Study consultants may be able to provide more detailed cost
estimates using bus operating cost models. The validity of such costs should be crosschecked with other data sources, including the range of values given in the national
statistics. Where possible, the co-operation and views of local bus operators should be
sought. The Confederation of Passenger Transport (CTP) may also be able to provide
assistance in estimating the costs of bus operation.
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TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
Rail Operating Costs
3.4.4
Information on rail operating cost assumptions can be obtained by discussion with the
Department.
4
Further Information
The following documents provide information that follows on directly from the key topics
covered in this Unit.
5
For information on:
See:
TAG Unit:
The Appraisal Process
The Overall Approach: The
Steps in the Process
TAG Unit 2.1
The Appraisal Process
TAG Unit 2.5
Modelling
Modelling
TAG Unit 3.1
Estimating and Treating
Scheme Costs
The Estimation and
Treatment of Scheme Costs
TAG Unit 3.5.9
References
M. Wardman, R. Batley, J. Laird, P. Mackie, A.S. Fowkes, G. Lyons, J. Bates and J.
Eliasson, Institute for Transport Studies, University of Leeds (2013), Valuation of Travel
Time Savings for Business Travellers
Faber Maunsell / AECOM (2008), M6T Research Study – Stage 2 Utilisation Surveys
P.J Mackie, M. Wardman, A.S Fowkes, G. Whelan, J Nellthorp and J Bates, Institute for
Transport Studies, University of Leeds (2003), Values of Travel Time Savings in the UK.
P. Wheat, M. Wardman and J. Bates, Institute for Transport Studies, University of Leeds
(2012), Advice on Statistical Confidence of Appraisal Non-Work Values of Time
P. Abrantes, M. Wardman, Institute for Transport Studies, University of Leeds (2010),
Meta-Analysis of UK Values of Time: An Update
Confederation of Passenger Transport (1999-2000), Focus on Public Transport.
Confederation of Passenger Transport (1999-2000), The Passenger Transport Industry
in Great Britain Facts.
ITEA Division, Department for Transport (2001), Transport Economics Note.
EEA Division, Department of Transport (1990-91), Review of Vehicle Operating Costs in
COBA.
Department for Transport (2005), Transport Statistics Great Britain.
HM Treasury (2013) Budget Report March 2013
ONS, Table IHXW, July 2013.
Office of Budget Responsibility Budget 2013 forecasts
Office of Budget Responsibility central projections (July 2013, Fiscal Sustainability Report).
Page 31
TAG Unit 3.5.6
Values of Time and Vehicle Operating Costs
GAD/ONS low migration projections for the United Kingdom
2008 household growth projections made by CLG.
http://www.communities.gov.uk/documents/housing/xls/table401.xls.
Office for National Statistics (2009) Population: national, 1971 onwards: Population Trends
http://www.statistics.gov.uk/statbase/ssdataset.asp?vlnk=9542&More=Y
http://www.gad.gov.uk/Demography%20Data/Population/2006/uk/wuk06cc.xls
6
Document provenance
This Transport Analysis Guidance (TAG) Unit was originally based on Appendix H of
Guidance on the Methodology for Multi-Modal Studies Volume 2 (DETR, 2000), and the
Transport Economics Note (DfT, 2001) and Netcen’s Carbon Emission and Fuel
Consumption Parameters for the National Transport Model (NETCEN, 2005).
Subsequently it has been updated regularly, usually once a year, in accordance with
forecasts of population, GDP and fuel prices elsewhere in Government. For details of past
issues, please see the Archive section of the WebTAG website.
The fuel consumption formulae were substantially updated in April 2011, and are now
based on Road vehicle emissions factors 2009.
The unit has been further updated, For Consultation, in November 2011, to include vehicle
operating costs for electric cars
The unit has been updated, In Draft, in May 2012. Monetary values have been converted to
2010 values and prices (previously 2002) and updated to include updated values following
the Budget in March 2012.
A October 2013 'in draft' release included updates to the values of travel time savings
using data from the 2008-2010 National Travel Survey; introduction of sensitivity testing
around those values; a change to the non-work value of travel time savings elasticity from
0.8 to 1.0; and updates to other values and growth rates consistent with the Budget and
accompanying OBR forecasts in 2013. This version of the Unit has now been released as
definitive guidance in January 2014.
Technical queries and comments on this Unit should be referred to:
Transport Appraisal and Strategic Modelling (TASM) Division
Department for Transport
Zone 2/25 Great Minster House
33 Horseferry Road
London SW1P 4DR
[email protected]
Page 32