Research Reports
Kansantaloustieteen laitoksen tutkimuksia, Nro 99:2003
Dissertationes Oeconomicae
ULLA LEHMIJOKI
Demographic Transition and Economic
Growth
ISBN 952-10-1218-8 (nid.)
ISBN 952-10-1217-X (pdf)
Yliopistopaino 2003
ethesis.helsinki.fi
Acknowledgements
The "Population Debate" asks whether demographic growth hampers or fosters
economic growth, and convincing arguments have been offered in support of both
views. In my thesis I try to show that, in the dynamic framework of demographic
transition, both cases are possible. Nevertheless, when working on my study, I
learned to appreciate why that most ardent of optimists, Julian Simon, argued in
1981 that people are "The Ultimate Resource".
I am thankful to Professor Seppo Honkapohja, whose continuous support made it
possible for me to undertake this study. His comprehensive approach to economic
theory helped me to set my work in a wider context of current economic analysis.
He encouraged me to face new, challenging questions concerning population
economics but also provided his help in my down-to-earth problems. I wish to
thank Professor Mikael Linden for his support to me, a theorist, to go through the
demanding phases of empirical research. His principle was that empirical work is
not so much appreciated on the basis of it being correctly or incorrectly, but rather,
well or poorly done. I also gratefully remember my meeting with Professor Seppo
Salo, who gave important mathematical advices to continue my work.
I am particularly indebted to my official examiners, Professors Matti Pohjola and
Pekka Ilmakunnas. Their thorough reviews have greatly increased the quality of
my thesis. Their suggestive and insightful comments helped me not only to find
better groundings for many arguments in my current work but also to shed light
onto questions that I hope to examine in my future research.
My research was conducted mainly while a lecturer in the Department of
Economics at the University of Helsinki. Due to the persistent work of the head of
the department, Professor Vesa Kanniainen, the personnel of the department,
myself included, enjoyed good research conditions even under ever increasing
pressures upon the scarce time of academics. The daily concerns of my academic
life were alleviated by the gentle care of administrator Ritva Teräväinen and
secretaries Hillevi Forsberg, Leena Harinen, and Päivi Leskinen. Among my
colleagues, I especially wish to thank Professor Tapio Palokangas for his helpful
comments in theoretical and practical problems that I encountered in my work, and
for his encouraging me to participate in broader academic conversations. I also
greatly enjoyed the academic comradery of Professor Anne Mikkola and research
assistants Mai Allo, Anu Alander, Anna-Leena Asikainen, and Helena Holopainen.
Our stimulating and pleasurable discussions ranged from new economic theories to
computational problems and from professional topics to everyday joys and
sorrows.
I would like to thank Professor Kari Pikänen for interesting discussions which
provided a welcome support to me in the field of demography; I returned several
times to his remark that different countries have experienced different transitions.
In my problems with “Survo” program I received valuable help from Lecturer Juha
Puranen; Doctors Heikki Ruskeepää and Pertti Näykki provided their help with the
program "Mathematica" in performing the parametric calculations of my thesis.
Nevertheless, the most demanding programming lied outside my abilities and was
performed by Yrjö Leino, Licentiate of Technology from CSC, the Finnish IT
center for science. The free-hand figures of the thesis were beautifully drawn by
Katri Uutela, Master of Social Sciences.
Finally, I want to thank my beloved ones for their companionship and help. My
life at home was supported by Marjatta. Without her work, it would not have been
possible for me to concentrate on my academic duties. I am thankful to my
husband, Jorma, who encouraged my academic interests throughout our busy years
of family life. I often asked him to tell me some of the many tales he knows in the
field of medicine; one of them is now repeated on the pages of this thesis. I also
benefited from the intellectual and practical help of my eldest daughter and son,
Maiju and Eero, who, together with Eero's wife Elina, helped me in my family
tasks. My problems in English were solved by my son-in-law, Christopher, who
taught me new ways to think about English language. Maiju, already holding a
Ph.D. in history, gave me a valuable example, but her younger siblings Lauri and
Marja, provided me a more equitable race when completing their examinations.
Our youngest daughter, Anni, has all this in front of her; I hope that my
experiences, in turn, might be of help for her. I dedicate my book with love to all
of you.
Helsinki, June 17, 2003
Ulla Lehmijoki
Contents
Chapter 1:
A Demographic Introduction ................................... 1-42
Chapter 2:
Demographic Transition in the Ramsey Model ....... 1-31
Chapter 3:
Learning by Living: Early Development ................. 1-28
Chapter 4:
Convergence, Income Inequality, and
Demographic Clubs ................................................. 1-30
Chapter 5:
Summary ................................................................... 1-5
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2.5
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2
1
1.5
1
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3
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Infant mortality
3
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shulrgv1
2
Change in fertility
1
0
-1
-2
1
3
5
7
9
Fertility
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Luhodqg +45<,/ Lwdo| +463,/ Pdowd +465,/ Qhwkhuodqgv +466,/ Qruzd| +467,/ Sru0
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Ghyhorsphqw/ Txduwhuo| Mrxuqdo ri Hfrqrplfv/ 438+5,/ 8348591
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ri Hfrqrplf Jurzwk/ 5/ 4591
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wkh ydoxh ri wkh surjudp e| x3 +f, +vhh 48,/ zkhuh hdfk f olhv rq sdwk D1 Qh{w/
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xqlwv/ hdfk ghfuhdvlqj wkh ydoxh ri surjudp e| x3 +f,1 Exw ehfdxvh hdfk f lv
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plqhv wkh qdo rxwfrph1 Lq wkh fdvh lq zklfk wkh vdggoh sdwk vwduwv iurp wkh
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grzq dqg ehfrphv wdqjhqw wr wkh nb @ 3olqh dqg wkh qxpehu ri vwhdg| vwdwhv
lqfuhdvhv wr wzr +qrw vkrzq,1 Dw wklv srlqw/ dq| voljkwhvw lqfuhdvh lq lqgxfhv d
orfdo elixufdwlrq dv wkh qxpehu ri vwhdg| vwdwhv lqfuhdvhv wr wkuhh1 Wkh hhfwv ri
sdudphwhu vkliwv wkdw ohdg wr fkdqjhv lq wkh qxpehu ri vwhdg| vwdwhv duh fdoohg
odujh hhfwv e| Krqndsrkmd dqg Wxuxqhq0Uhg +5335,1 Dv ixuwkhu lqfuhdvhv/
wkh frruglqdwhv ri vwhdg| vwdwhv fkdqjh exw wkhlu qxpehu vwd|v dv wkuhh1 Wkdw
lv/ vpdoo exw qr odujh hhfwv wdnh sodfh1 Hyhq vr/ wkh vwuxfwxuh ri wkh yhfwru
hog vdwlvi|lqj +<,0+43, fkdqjhv frqwlqxrxvo| dqg lq wkh duhd ri lqwhuhvw/ ohiw
ri vwduwv wr uxq pruh dqg pruh iurp wkh qruwkzhvw dv wkh X sduw ri wkh
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wrzdug vwhdg| vwdwh 6 jhwv pruh fxuyhg dqg uxqv forvhu wr vwhdg| vwdwh 41 Iru
vrph fulwlfdo ydoxh ri / E uxqv rxw ri vwhdg| vwdwh 4/ dqg iru odujhu vwloo/ E
vsludov rxw ri vwhdg| vwdwh 51 Wkhuhiruh/ lq dgglwlrq wr vpdoo dqg odujh hhfwv/
wkh sdudphwhu dovr kdv dq hhfw wkdw zh fdoo d joredo hhfw1 Sdqhov e g
lq Iljxuh : looxvwudwh wkh fkdqjhv lq wkh vorsh ri wkh vdggoh sdwkv lqgxfhg e|
vxffhvvlyh lqfuhdvhv lq 1 Sdqho e uhihuv wr wkh orzhvw ydoxh ri dqg wr wkh
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Iljxuh := Wkh lvrfolqhv +sdqho d, dqg wkh vwdeoh vdggoh sdwkv +sdqhov e g, iru
sdudphwhuv @ +3=339> 3=33<> dqg 3=37,/ @ 6;3/ dqg @ 4331 Wkh ydoxh iru
lqfuhdvhv lq wkh gluhfwlrq ri wkh duurz lq sdqho d1 Pdwkhpdwlfd 71351 surjudp
wr fdofxodwh dqg gudz wkh jxuh lv dydlodeoh iurp wkh dxwkru1
rwkhu wzr lvrfolqhv lq sdqho d uhvshfwlyho|1
Wkh uroh ri lv wr vkliw wkh X sduw ri wkh lvrfolqh fb @ 3 krul}rqwdoo| wr wkh
uljkw dv lqfuhdvhv1 Odujh fdslwdo vwrfnv gxulqj wkh wudqvlwlrq whqg wr lqfuhdvh
wkh srvvlelolw| ri d sryhuw| wuds1 Wkh h{sodqdwlrq lv irxqg lq wkh ghfuhdvlqj
pdujlqdo surgxfw ri fdslwdo= li wkh fdslwdo vwrfn lv odujh gxulqj wkh wudqvlwlrq/
wkh orz pdujlqdo surgxfw ri d xqlw lqfuhdvh lq fdslwdo lv hdvlo| hdwhq xs e| dq
lqgxfhg lqfuhdvh lq srsxodwlrq jurzwk udwh/ dqg wkh ghhshqlqj ri fdslwdo lv qrw
srvvleoh1 Iru dq| jlyhq dqg > vpdoo ydoxhv ri pdnh wkh vorsh q+n, vwhhshu1
Wklv phdqv wkdw wkh srsxodwlrq jurzwk udwh vwurqjo| uhdfwv wr dq lqfuhdvh lq
shu fdslwd fdslwdo dqg lqfrph1 Iru q3 +n, A 3> d xqlw lqfuhdvh lq fdslwdo lv wkhq
dffrpsdqlhg e| d odujh lqfuhdvh lq wkh srsxodwlrq jurzwk udwh/ dqg wklv whqgv
wr ohdg wkh hfrqrp| wrzdug d sryhuw| wuds1
Iljxuh ; vkrzv wkh frpelqhg hhfw ri sdudphwhuv > > dqg rq wkh g|0
qdplfv ri wkh dxjphqwhg prgho1 Wkh wzr vxuidfhv glylgh wkh vsdfh lqwr wkuhh
duhdv1 Lq duhd L/ wkh ydoxhv ri dqg duh orz exw wkdw ri lv kljk1 Wklv lv
wkh zhdn fdvh ri ghprjudsklf wudqvlwlrq1 Lq wklv fdvh/ wkh wudqvlwlrq wdnhv sodfh
dw orz vwrfnv ri surgxfwlyh fdslwdo/ wkh srsxodwlrq jurzwk lv qrw yhu| vhqvlwlyh
wr lqfrph +fdslwdo,/ dqg krogv orz ydoxh hyhq lq lwv shdn1 Rqo| d vlqjoh vwhdg|
vwdwh h{lvwv/ dqg lw lv rswlpdo wr surfhhg wrzdug lw iurp doo lqlwldo fdslwdo vwrfnv1
Lq duhd LLL/ wkh wudqvlwlrq wdnhv sodfh zlwk uhodwlyho| odujh fdslwdo vwrfnv/ shdn
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vwhdg| vwdwh1 Duhd LL= wkuhh vwhdg| vwdwhv/ wkh vrxwk0zhvwhuq vdggoh sdwk E
vwduwv iurp wkh ruljlq1 Duhd LLL= wkuhh vwhdg| vwdwhv/ wkh vrxwk0zhvwhuq vdggoh
sdwk E hpdqdwhv vsludoo| iurp vwhdg| vwdwh 51 Wkh jxuh zdv fdofxodwhg dqg
gudzq e| \umù Ohlqr iurp FVF1
srsxodwlrq jurzwk lv kljk/ dqg lwv uhdfwlrq wr lqfrph dqg lqfuhdvh lq fdslwdo lv
lqwhqvlyh1 Lq wklv vwurqj fdvh ri ghprjudsklf wudqvlwlrq/ d sryhuw| wuds dulvhv/
dqg wkh hfrqrp| fdq hvfdsh lw rqo| li lwv surgxfwlyh fdslwdo lv udlvhg deryh wkh
wkuhvkrog ydoxh e| vrph h{rjhqrxv idfwru olnh iruhljq dlg1 Iljxuh < jlyhv d furvv
vhfwlrq ri Iljxuh ; iru @ 4331
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kdv ehhq zhdn1 Wkh uhohydqw txhvwlrq lv/ zkhwkhu ghprjudsklf wudqvlwlrq lq
Vlqjdsruh ru Qljhuld kdv ehhq vwurqj1 Lq wkh fdvh ri Vlqjdsruh/ wkh dqvzhu lv
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vslwh ri lwv yhu| kljk shdn srsxodwlrq jurzwk udwh/ lw kdv reylrxvo| dyrlghg wkh
wuds1 Ixuwkhupruh/ lw lv olnho| wkdw Qljhuld zloo dovr gr vr1 Hyhq li Vlqjdsruh
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srsxodwlrq jurzwk udwhv/ wkh frpelqdwlrq ri wkh ghprjudsklf sdudphwhuv lq
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53
0.05
0.04
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II
η
0.03
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0.01
0
0
200
400
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600
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0.04
Weak
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P 150
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100
200
300
400
500
600
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0.02
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250
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100
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0.03
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0.02
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10
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time
250
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250
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|
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Sursrvlwlrq 6 +Shulrg 4<<805363,1 Orzhu srsxodwlrq jurzwk udwhv ohdg wr
orzhu lqhtxdolw| ri lqfrphv1
Wkh lqfrph lqhtxdolw| lq wkh vdpsoh ri 443 frxqwulhv iurp 4<93 wr 4<<8
fdq eh fdofxodwhg gluhfwo| e| xvlqj wkh gdwd ghvfulehg rq sdjh 71 Wkh Xqlwhg
Qdwlrqv +5333, surylghv surmhfwlrqv iru ixwxuh srsxodwlrq jurzwk udwhv1 Xvlqj
wkhvh surmhfwlrqv dqg wkh irxu ghprjudsklf foxev zlwk nqrzq hfrqrplf jurzwk
udwhv gxulqj 4<930<8/ zh hvwlpdwh wkh jurzwk udwhv iurp 4<<8 wr 5363 iru hdfk
frxqwu| lq wkh vdpsoh1 Ehfdxvh wkh Xqlwhg Qdwlrqv surylghv wkuhh yduldqwv Orz/ Phglxp/ dqg Kljk zh duh deoh wr ghulyh wkuhh hvwlpdwhv iru ixwxuh
lqfrphv dqg wkuhh phdvxuhv ri lqfrph lqhtxdolw| iru hdfk yduldqw1 Zh vwduw e|
fdofxodwlqj ixwxuh lqfrphv1
614
Ixwxuh Lqfrphv
Lq wkh ixwxuh/ srsxodwlrq jurzwk udwhv ghfuhdvh doprvw hyhu|zkhuh1 Wklv phdqv
wkdw frxqwulhv lq wkh vdpsoh pryh iurp rqh ghprjudsklf foxe wr dqrwkhu1 Zh
fdofxodwh wkhvh pryhphqwv iru hdfk frxqwu| rq wkh edvlv ri zkdw lv nqrzq derxw
ixwxuh srsxodwlrq jurzwk udwhv1 E| dvvxplqj wkdw hfrqrplf jurzwk udwhv lq hdfk
foxe uhpdlqv iurp 4<<8 wr 5363 dv wkh| zkhuh iurp 4<93 wr 4<<8/ zh ghulyh wkh
ixwxuh lqfrphv iru hdfk frxqwu|1
49
Wklv pljkw eh vshfxodwlyh1 Lw lpsolflwo| dvvxphv wkdw hyhu|wklqj lq hfrqrplf
jurzwk ghshqgv rq ghprjudsk|1 Li wklv zhuh wkh fdvh/ nqrzlqj wkh ixwxuh gh0
prjudsklf vlwxdwlrq ri d frxqwu| zrxog eh doo wkdw zh zrxog qhhg wr pdnh ydolg
surmhfwlrqv iru ixwxuh lqfrphv1 Iruwxqdwho|/ zh fdq dowhuqdwlyho| dvvxph wkdw
wkhuh h{lvwv qr v|vwhpdwlf uhdvrq iru wkh foxe0vshflf jurzwk udwhv iurp 4<<8
wr 5363 wr eh glhuhqw iurp wkh vdph jurzwk udwhv iurp 4<93 wr 4<<81 Lq wklv
fdvh/ rxu iruhfdvwv pljkw eh xqfhuwdlq/ exw qrw eldvhg1
N
4
A
C
D
2.0275
B
-1
-3
-1.7
-0.105
2
DN
Iljxuh := Wkh Orz Yduldqw surmhfwlrq iru wkh ghprjudsklf vlwxdwlrq lq wkh
ixwxuh1
Wkh wkuhh XQ0surmhfwlrqv iru ixwxuh srsxodwlrq jurzwk udwhv duh jlyhq lq
wkuhh yduldqwv/ zklfk duh
Orz Yduldqw>
Phglxp Yduldqw>
Kljk Yduldqw>
Wkh ghwdlov ri wkh ghqlwlrqv duh jlyhq lq Dsshqgl{ E1 Zh frqfhqwudwh
rq glhuhqfhv ehwzhhq Kljk dqg Orz Yduldqwv/ exw uhsruw wkh uhvxowv iru wkh
Phglxp Yduldqw iru wkh vdnh ri frpsohwhqhvv1
Ixwxuh lqfrphv duh ghulyhg dv iroorzv= Iluvw/ iru d jlyhq yduldqw/ fdofxodwh
wkh fkdqjh lq srsxodwlrq jurzwk udwh iurp 4<<8 wr 5363 dqg dyhudjh srsxodwlrq
jurzwk udwh iurp 4<<8 wr 5363 iru hdfk frxqwu|1 Wkhq orfdwh hdfk frxqwu| lq
rqh ri wkh irxu foxev ghulyhg deryh1 Iljxuhv : dqg ; ghslfw ixwxuh ghprjudsklf
4:
N
4
A
C
D
2.0275
B
-1
-3
-1.7
-0.105
2
DN
Iljxuh ;= Wkh Kljk yduldqw surmhfwlrq iru wkh ghprjudsklf vlwxdwlrq lq wkh
ixwxuh1
vlwxdwlrqv xqghu Orz dqg Kljk Yduldqwv1 Rqfh hdfk frxqwu| lv orfdwhg wr lwv
dssursuldwh foxe/ lwv jurzwk udwh iurp 4<<8 wr 5363 lv dvvxphg wr eh wkh dyhudjh
jurzwk udwh fdofxodwhg iru wkdw foxe iurp 4<93 wr 4<<81 Wkhq/ fdofxodwh/ iru hdfk
yduldqw
JGS {{ @ JGS <8 H{s+jm +{{ 4<<8,,>
lq zklfk JGS lv wkh shu fdslwd lqfrph/ {{ lv wkh fdohqgdu |hdu iurp 5333 wr
5363/ dqg jm lv wkh foxe0vshflf jurzwk udwh1 Uhshdw wklv iru hdfk yduldqw wr
kdyh wkuhh glhuhqw lqfrph surmhfwlrqv iru hdfk yh |hduv ehwzhhq 5333 dqg 5363
dqg iru hdfk frxqwu|1 Wdeoh 6 vxppdul}hv wkh ghprjudsklf dqg wkh hfrqrplf
ghyhorsphqw lq wkh sdvw dqg lq wkh ixwxuh1
Erwk wrwdo srsxodwlrq dqg dyhudjh JGS shu fdslwd lqfuhdvhg vwhdglo| iurp
4<93 wr 4<<81 Reylrxvo|/ rxu sodqhw vxssolhg dq lqfuhdvlqj zhoo0ehlqj wr dq lq0
fuhdvlqj qxpehu ri shrsoh1 Dffruglqj wr rxu iruhfdvwv/ wklv wuhqg zloo frqwlqxh
iurp 4<<8 wr 5363/ exw glhuhqfhv ehwzhhq wkh yduldqwv duh frqvlghudeoh1 Lq
5363/ wrwdo srsxodwlrq lq wkh vdpsoh ri 443 frxqwulhv lv 49 ( odujhu dqg dyhudjh
JGS shu fdslwd lv 4< ( vpdoohu xqghu wkh Kljk Yduldqw wkdq xqghu wkh Orz
Yduldqw1 Wkhuhiruh/ erwk kxpdq dqg hfrqrplf dvshfwv idyru orz srsxodwlrq
jurzwk udwh lq wkh ixwxuh1 Lq dgglwlrq/ dvvxplqj wkdw ghwhulrudwlrq ri hqyl0
urqphqw dqg vx!flhqf| ri qdwxudo uhvrxufhv duh uhodwhg wr srsxodwlrq jurzwk/
orz srsxodwlrq jurzwk pljkw kdyh srvlwlyh hhfwv qrw frpsohwho| glvfryhuhg lq
wklv sdshu1 Iljxuh < vkrzv wkh hqwluh wlph sdwk iru srsxodwlrq dqg shu fdslwd
4;
\hdu
4<93
4<98
4<:3
4<:8
4<;3
4<;8
4<<3
4<<8
Srsxodwlrq
JGS
5 686
5 599
5 938
5 9<5
5 <33
6 567
6 53;
6 99<
6 834
7 4<6
6 ;4<
7 687
7 494
7 :<;
7 7;;
8 483
\hdu
Orz
5333
5338
5343
5348
5353
5358
5363
Srsxodwlrq
JGS
7 ;35
9 58<
8 3:<
: 549
8 65:
; 656
8 884
< 938
8 :85
44 3<3
8 <5<
45 ;47
9 39;
47 ;47
Srsxodwlrq
JGS
7 ;35
9 54;
8 449
: 456
8 759
; 497
8 :64
< 697
9 357
43 :7:
9 637
45 675
9 898
47 4;7
Srsxodwlrq
JGS
7 ;35
9 397
8 484
9 :;5
8 849
: 935
8 ;<8
; 86;
9 5;3
< 939
9 99;
43 ;5:
: 38<
45 556
Phglxp
Kljk
Wdeoh 6= Wrwdo srsxodwlrq +lq ploolrqv, dqg dyhudjh shu fdslwd JGS +lq lqwhu0
qdwlrqdo 4<;8 grooduv, lq wkh vdpsoh1
lqfrphv1
615
Lqhtxdolw| ri Lqfrphv
Xqlwhg Qdwlrqv srsxodwlrq surmhfwlrqv duh vxssolhg lq shulrgv ri yh |hduv1
Wkhuhiruh/ wkh wlph vhulhv whvw iru lqfrph frqyhujhqfh lq H{huflvh L fdqqrw eh
uhshdwhg khuh1 Lqvwhdg/ wr vwxg| wkh glvshuvlrq ri ixwxuh lqfrphv/ zh duh erxqg
wr xvh pruh wudglwlrqdo dqg gluhfw phdvxuhv ri lqhtxdolw|/ vxfk dv surylghg e|
Oruhq} +4<38,/ Jlql +4<69,/ dqg Wkhlo +4<9:,1 Wkhvh phdvxuhv frqfhqwudwh rq
hvwlpdwlrq ri dq lqgh{ iru wkh lqhtxdolw| ri wkh lqfrph glylvlrq lq d jlyhq |hdu1
Wkh ghvludeoh surshuwlhv iru wklv nlqg ri lqgh{ duh glvfxvvhg e| Vhq +4<:6,/
Dwnlqvrq +4<:3,/ Doolvrq +4<:;,/ dqg Gdvjxswd hw do1 +4<:6,1 Iluvw/ dq lqgh{ ri
lqhtxdolw| kdv wr phhw wkh Sljrx0Gdowrq frqglwlrq/ zklfk vwdwhv wkdw dq| wudqv0
ihu iurp d ulfk shuvrq wr d srru shuvrq vkrxog ghfuhdvh wkh ydoxh ri wkh lqgh{
+vhh Sljrx 4<45 dqg Gdowrq 4<53,1 Vhfrqg/ wkh lqgh{ vkrxog eh vfdoh lqyduldqw/
phdqlqj wkdw li hyhu|rqh*v lqfrph lv pxowlsolhg e| d frqvwdqw/ wkh ydoxh ri wkh
lqgh{ lv xqfkdqjhg1 Lq qrplqdo whupv wklv uhtxluhphqw lv lqglvsxwdeoh= zkhwkhu
wkh lqfrphv duh phdvxuhg lq |hq ru grooduv grhv qrw kdyh dq| hhfw rq lqhtxdo0
lw|1 Uhdo sursruwlrqdwh lqfuhdvhv duh pruh sureohpdwlf1 Li hyhu|rqh*v lqfrph
lqfuhdvhv e|/ vd|/ 43 (/ wkh udwlrv ri lqfrphv duh ohiw xqfkdqjhg exw wkh ulfk
jdlq lq devroxwh whupv1 Vhq +4<:6,/ krzhyhu/ dujxhv wkdw wklv zrxog qrw eh qhf0
hvvdu|1 Wklug/ wkh lqgh{ vkrxog eh lqyduldqw wr wkh vl}h ri wkh srsxodwlrq/ dqg
irxuwk/ lw vkrxog eh prvw vhqvlwlyh wr wudqvihuv lq wkh orzhu hqg ri wkh lqfrph
glylvlrq1 Wkh odwwhu uhtxluhphqw vd|v wkdw wkh vrfldo zhoiduh ixqfwlrq/ lpsolhg
e| wkh lqgh{/ vkrxog eh vwulfwo| frqfdyh +vhh Dwnlqvrq 4<:3 dqg Vhq 4<:6,1
Wkuhh lqglfhv phhwlqj wkh uvw wkuhh uhtxluhphqwv duh wkh frh!flhqw ri yduld0
4<
16000
GDP(low)
14000
GDP(high)
12000
10000
8000
Pop.(high)
Pop.(low)
6000
4000
2000
1960
1995
2030
Iljxuh <= Wrwdo srsxodwlrq dqg shu fdslwd JGS xqghu Orz dqg Kljk Yduldqwv1
wlrq/ wkh Wkhlo lqgh{/ dqg wkh Jlql frh!flhqw1 Lq wkh frqwh{w ri lqfrph glylvlrq
ehwzhhq frxqwulhv/ wkh Jlql frh!flhqw/ J/ lv wkh dyhudjh devroxwh glhuhqfh eh0
wzhhq doo sdluv ri lqfrphv |l dqg |m ri frxqwulhv uhodwlyh wr wkh phdq ri wkh
vdpsoh lqfrph/ =
J @
4
q5
Sq
l@4
q
@
Sq
m@4
m|l |m m
5
+:,
q.4
5 [
l |l >
q5 l@4
q
lq zklfk q lv wkh qxpehu ri wkh frxqwulhv dqg l lv dq lqgh{ uxqqlqj iurp wkh
srruhvw wr wkh ulfkhvw frxqwu|1 Wkh Jlql frh!flhqw/ krzhyhu/ grhv qrw phhw wkh
uhtxluhphqw ri wkh vhqvlwlylw| ri wudqvihuv1 Wr vhh wklv/ dvvxph wkdw zh jlyh d
wudqvihu ri k grooduv iurp frxqwu| p zlwk lqfrph |p wr frxqwu| n zlwk lqfrph
|n / vxfk wkdw lqlwldoo| |n ? |p 1 Ohw J dqg J3 eh wkh Jlql frh!flhqw ehiruh
dqg diwhu wkh wudqvihu/ dqg ohw o @ 4> 5> > q eh dq lqgh{ vxfk wkdw lw lqfoxghv
doo qxpehuv exw p dqg n1 Lq wklv fdvh
J3 @
q
5 [
q.4
^
=
o |o . n+|n . k, . p+|p k,` 5
q q
o@4
3
5
q5 +n
p,k1 Wkhuhiruh/ wkh Jlql frh!flhqw rqo| ghshqgv rq
Wkhq J J @
wkh glhuhqfh ri wkh udqnlqj ehwzhhq frxqwulhv1 Iru lqwhuqdwlrqdo frpsdulvrqv/
krzhyhu/ wkh olqhdulw| ri wkh lpsolhg zhoiduh ixqfwlrq vhhpv wr eh phuho| d
ghvludeoh surshuw| ehfdxvh lw lv qrw fohdu zkdw vkrxog eh wkh lqwhusuhwdwlrq iru
vxfk d ixqfwlrq dw wkh lqwhuqdwlrqdo ohyho1 Iru wklv uhdvrq Jlql frh!flhqw lv xvhg
lq wklv sdshu1
53
\hdu
43(
8(
4<93
4<98
4<:3
4<:8
4<;3
4<;8
4<<3
4<<8
31888<
318944
318:89
318:;9
318:7:
318:<8
318:88
318:<9
318:37
318:99
318886
31893:
31889;
31895:
3185;4
31866;
\hdu
Orz
43(
8(
Phglxp
43(
8(
Kljk
43(
8(
5333
5338
5343
5348
5353
5358
5363
3185<5
318686
31863<
3186:5
318666
3186<;
318695
31875<
3186<;
318799
318774
31883<
3187<4
31888;
318633
318693
318653
3186;6
318675
31873;
31869<
31876;
318735
3187:7
318775
318846
3187;;
31888:
318548
31859<
318493
318546
31844;
3184;5
318436
3184:5
3183<6
318498
3183;;
318498
3183<5
3184:5
Wdeoh 7= Wkh Jlql frh!flhqwv1
Zh fdofxodwh Jlql frh!flhqwv iru 443 frxqwulhv lq wkh vdpsoh wr hydoxdwh wkh
lqhtxdolw| ri lqfrphv lq wkh sdvw +iurp 4<93 wr 4<<8,/ dqg lq wkh ixwxuh +iurp
5333 wr 5363,1 Wkh ydoxhv duh jlyhq iru hyhu| iwk |hdu1 Wkh ixwxuh ydoxhv duh
fdofxodwhg iru Orz/ Phglxp/ dqg Kljk Yduldqwv1
Zh dvvxph wkdw doo lqkdelwdqwv lq d frxqwu| hduq wkh dyhudjh shu fdslwd
lqfrph lq wkdw frxqwu|1 Ehfdxvh wkh vl}h ri wkh frxqwulhv lq wkh vdpsoh ydulhv/
wkh srsxodwlrq ri wkh vdpsoh lv glylghg lqwr iudfwlohv1 Erwk 43 ( dqg 8 (
iudfwlohv duh xvhg1 Wkh frxqwu| vshflf lqfrphv |l lq htxdwlrq +:, duh uhsodfhg
e| lqfrph vkduhv ri wkh iudfwlohv vr wkdw q uhihuv wr wkh qxpehu ri iudfwlohv
+43 ru 53,1 Wr fdofxodwh wkh lqfrph vkduhv ri wkh iudfwlohv/ orfdwh wkh srruhvw
43 ( +8 (, ri wkh srsxodwlrq wr wkh uvw iudfwloh dqg dgguhvv wkh lqfrph hduqhg
e| wkhvh shrsoh wr wkdw iudfwloh1 Frqwlqxh lq wklv zd| iurp iudfwloh wr iudfwloh1
Qrwh wkdw vrph iudfwlohv frqwdlq vhyhudo frxqwulhv exw odujh frxqwulhv +XVD/
Fklqd/ dqg Lqgld, duh glylghg ehwzhhq vhyhudo iudfwlohv1 Wdeoh 7 uhsruwv wkh
Jlql frh!flhqwv iru erwk 43 ( dqg 8 ( iudfwlohv1
Wdeoh 7 vkrzv wkdw wkh ydoxhv ri 8 ( iudfwloh Jlql frh!flhqwv duh odujhu
wkdq 43 ( iudfwloh ydoxhv1 Wklv lv lq olqh zlwk uhvxowv irxqg e| Sdun +4<<:,1
Iljxuh 43 vkrzv wkh wuhqgv ri wkh Jlql frh!flhqw iru 8 ( iudfwlohv1 Phdvxuhg
e| Jlql frh!flhqwv/ lqhtxdolw| lqfuhdvhg iurp 4<93 wr 4<98/ lv frqvwdqw ehwzhhq
4<9804<;3 dqg ghfuhdvhg e| 4<<81
Sursrvlwlrq 5 dujxhv wkdw lqfrph lqhtxdolw| ghfuhdvhv dv wkh srsxodwlrq
jurzwk udwh lq ghyhorslqj frxqwulhv vwduwv wr ghfuhdvh1 Doo frxqwulhv lq foxev
D> F/ dqg G zhuh ghyhorslqj frxqwulhv dw wkh ehjlqqlqj ri wkh shulrg +vhh
Dsshqgl{ D,1 Wkh srsxodwlrq jurzwk lq wkhvh frxqwulhv lq |hduv 4<9304<<8 lv
jlyhq lq Iljxuh 441 Wkh uhvhpeodqfhv wr wkh Jlql frh!flhqwv lq Iljxuh 43 duh
dssduhqw1 Wklv jlyhv vrph vxssruw wr wkh lqyhuwhg0X k|srwkhvlv dv h{suhvvhg lq
Sursrvlwlrq 51 Xqiruwxqdwho|/ hyhq li d sdlu ri Jlql frh!flhqwv fdq eh frpsduhg
e| fdofxodwlqj wkhlu frqghqfh lqwhuydov +vhh ehorz,/ qr whvwlqj surfhgxuh iru
54
0.7
0.6
Low
High
0.5
0.4
1960
1970
1980
1990
2000
2010
2020
2030
Iljxuh 43= Wuhqgv ri Jlql frh!flhqw iru Orz dqg Kljk Yduldqw/ 8( iudfwlohv1
d vhulhv ri vxfk frh!flhqwv lv nqrzq wr xv/ dqg zh duh erxqg wr edvh rxu
d!updwlyh frqfoxvlrqv lq uhodwlrq wr Sursrvlwlrq 5 rq wkh judsklfdo lqirupdwlrq
lq Iljxuhv 43 dqg 441
Iurp 4<<8 wr 5363 lqvwhdg/ wkh uhvxowv jlyhq lq Wdeoh 7/ dqg looxvwudwhg lq
Iljxuh 43/ frqiurqw wkh lqyhuwhg0X k|srwkhvlv irupxodwhg lq Sursrvlwlrq 61 Orz/
qrw kljk/ srsxodwlrq jurzwk udwh ohdgv wr juhdwhu lqhtxdolw| ri wkh lqfrphv lq
wkh vdpsoh1 Wklv lv dq xqh{shfwhg uhvxow1 Wr kdyh d ghhshu lqvljkw/ frqvlghu
frxqwulhv wkdw zhuh lq foxev D> F/ dqg G gxulqj shulrg 4<9304<<8 dv ghyhors0
lqj frxqwulhv/ dqg frxqwulhv lq foxe E dv ulfk frxqwulhv1 Wr vhh zklfk zdv wkh
lqfrph lqhtxdolw| zlwklq ghyhorslqj frxqwulhv dqg zlwklq ulfk frxqwulhv xqghu
Orz dqg Kljk Yduldqwv/ fdofxodwh wkh dssursuldwh Jlql frh!flhqwv zlwklq wkhvh
vxe0vdpsohv1 Zlwklq ghyhorslqj frxqwulhv +foxev D> F/ dqg G,/ wkh frh!flhqwv
zkhuh 3=6<;3 dqg 3=743:/ vr wkdw lqhtxdolw| zlwklq ghyhorslqj frxqwulhv zdv
odujhu xqghu Kljk Yduldqw1 Zlwklq ulfk frxqwulhv +foxe E,/ krzhyhu/ wkh qxp0
ehuv duh 3=77;; dqg 3=6<;4/ dqg wkh lqfrph lqhtxdolw| zlwklq ulfk frxqwulhv lv
odujhu xqghu Orz wkdq xqghu Kljk Yduldqw1 Wkh uhdvrq lv wkdw XVD dqg Ox{0
hperxuj/ wkh wzr ulfkhvw frxqwulhv lq wkh vdpsoh/ vwd| lq foxe E +jurzwk udwh
5=:;43 (, xqghu Orz Yduldqw/ exw pryh wr foxe G +jurzwk udwh 3=8956 (, xqghu
Kljk Yduldqw/ dqg wkh lqhtxdolw| zlwklq E ghfuhdvhv ehfdxvh ri wklv pryh1
Wkh pryh ri +dw ohdvw vrph ri, wkh ulfkhvw frxqwulhv wr xqidyrudeoh ghpr0
judsklf foxev pljkw eh uhdoo| wuxh lq wkh ixwxuh1 Wkh sureohp lv wkdw wkh foxev/
fuhdwhg rq wkh edvlv ri lqirupdwlrq iurp 4<93 wr 4<<8/ pljkw qrw fdswxuh doo wkh
ghprjudsklf foxev/ wkdw pd| eh suhvhqw lq wkh ixwxuh1 Wkh hfrqrplf jurzwk
udwh dqg wkh erughuolqhv ri foxe G/ wr zklfk XVD dqg Ox{hperxuj duh fodv0
vlhg xqghu wkh Kljk Yduldqw/ zdv lghqwlhg dprqj lqlwldoo| srru +ghyhorslqj,
frxqwulhv +vhh Dsshqgl{ D, zlwk hyhu lqfuhdvlqj frkruwv ri |rxqj shrsoh +vhh
55
2.7
N
2.6
2.5
2.4
2.3
60
65
70
75
80
85
90
95
Iljxuh 44= Srsxodwlrq jurzwk udwh lq foxev D> F/ dqg G iurp 4<93 wr 4<<81
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Wudqvlwlrq= dq Lfrqrfodvwlf Ylhz/ Srsxodwlrq Vwxglhv/ 74+4,/ 8631
Hdvwhuolq/ U1 D1 +4<:;,= Wkh Hfrqrplfv dqg Vrflrorj| ri Ihuwlolw|= D V|q0
wkhvlv/ lq +Wloo| 4<96,/ ss1 8:4661
Hydqv/ S1/ dqg J1 Nduudv +4<<9,= Frqyhujhqfh Uhylvlwhg/ Mrxuqdo ri Prq0
hwdu| Hfrqrplfv/ 6:/ 57<5981
Jrrgiulhqg/ P1/ dqg M1 PfGhuprww +4<<8,= Hduo| Ghyhorsphqw/ Dphu0
lfdq Hfrqrplf Uhylhz/ ;8/ 4494661
Nx}qhwv/ V1 +4<9:,= Srsxodwlrq dqg Hfrqrplf Jurzwk/ Surfhhglqjv ri wkh
Dphulfdq Sklorvrsklfdo Vrflhw|/ 5+6,/ 4:34<61
Ohvwkdhjkh/ U1 +4<;6,= D Fhqwxu| ri Ghprjudsklf dqg Fxowxudo Fkdqjh
lq Zhvwhuq Hxursh= Dq H{sorudwlrq ri Xqghuo|lqj Glphqvlrqv/ Srsxodwlrq
dqg Ghyhorsphqw Uhylhz/ <+6,/ 7447681
Pdvrq/ N1 R1 +4<<:,= H{sodlqlqj Ihuwlolw| Wudqvlwlrqv/ Ghprjudsk|/ 67+7,/
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Qrwhvwhlq/ I1 Z1 +4<78,= Srsxodwlrq= Wkh Orqj Ylhz/ lq +Vfkxow} 4<78,1
Urvhur0El{e|/ O1/ dqg M1 E1 Fdvwhuolqh +4<<6,= Prghoolqj Glxvlrq Hi0
ihfwv lq Ihuwlolw| Wudqvlwlrq/ Srsxodwlrq Vwxglhv/ 7:+4,/ 47:49:1
Vdod00Pduwlq/ [1 [1 +4<<9,= Wkh Fodvvlfdo Dssurdfk wr Frqyhujhqfh Dqdo|0
vlv/ Hfrqrplf Mrxuqdo/ 439/ 434<43691
Vfkxow}/ S1 W1 +hg1, +4<78,= Irrg iru wkh Zruog1 Xqlyhuvlw| ri Fklfdjr Suhvv/
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Vnled/ D1 +4<:;,= Rswlpdo Jurzwk zlwk d Frqyh{0Frqfdyh Surgxfwlrq Ixqf0
wlrq/ Hfrqrphwulfd/ 79+6,/ 85:86<1
Wloo|/ F1 +4<96,= Klvwrulfdo Vwxglhv lq Fkdqjlqj Ihuwlolw|1 Sulqfhwrq Xqlyhuvlw|
Suhvv/ Sulqfhwrq/ Q1M1
X}dzd/ K1 +4<9;,= Wlph Suhihuhqfh/ wkh Frqvxpswlrq Ixqfwlrq/ dqg Rswl0
pxp Dvvhw Kroglqjv/ lq +Zroih 4<9;,/ fkds1 541
Zroih/ M1 +hg1, +4<9;,= Ydoxh/ Fdslwdo/ dqg Jurzwk1 Doglqh/ Fklfdjr1
8