2021-2070年日本人口预测报告（2023年修订版）

PopulationProjectionsforJapan(2023revision):2021to2070Appendix:AuxiliaryProjections2071to2120

Contents

KeyMessages(4)

IOverviewofthePopulationProjectionsforJapan(7)

IISummaryoftheProjectionResults(7)

[ProjectionResultsforMedium-,High-,andLow-Fertility(Medium-Mortality)](7)

1.TrendsinTotalPopulation(7)

2.TrendsintheSizeandCompositionofthePopulationbytheMajorThreeAgeGroups(8)3.Trendsindependencyratio(9)

4.ChangesinthePopulationPyramid(10)

[ProjectionResultsforMedium-Fertility(High-andLow-Mortality)](10)

1.SummaryofProjectionResultswithHigh-MortalityAssumption(10)

2.SummaryofProjectionResultswithLow-MortalityAssumption(10)

[ProjectionResultsforHigh-andLow-Fertility(High-,Low-Mortality)](11)

IIISummaryoftheMethodUsedforPopulationProjections(11)

1.BasePopulation(11)

2.AssumptionsforFertilityRatesandSexRatioatBirth(11)

3.AssumptionsforSurvivalRates(FutureLifeTable)(15)

4.AssumptionsforInternationalMigrationRates(Numbers)(16)

5.Long-rangeAuxiliaryProjections,ProjectionsfortheJapanesePopulation,andConditionalPopulationProjections(17)

SummaryofProjectionResults(medium-mortalityprojection)(19)

SummaryofAssumptions(20)

IVProjectionResultsandAssumptions(23)

<ProjectionResultsforMedium-,High-,andLow-Fertility(Medium-Mortality)≫(23)

<ProjectionResultsforMedium-Fertility(Medium-,High-,andLow-Mortality)≫(35)

<ComparisonofProjectionResultswithDifferentAssumptions≫(41)

<Assumptions≫(47)

<Long-rangeAuxiliaryProjections≫(55)

<ProjectionsfortheJapanesePopulationandFertilityAssumptions≫(63)

<ConditionalPopulationProjections≫(71)

AppendixTotalPopulation,populationbythethreeagegroups:1950-2020(79)

NationalInstituteofPopulationandSocialSecurityResearchinJapan

https://www.ipss.go.jp/index-e.asp

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ListofTablesandFigures

SummaryofProjectionResults(medium-mortalityprojection)(19)

SummaryofFertilityAssumptions(20)

SummaryofMortalityAssumptions(21)

SummaryofInternationalMigrationAssumptions(21)

[ProjectionResultsforMedium-,High-,andLow-Fertility(Medium-Mortality)]

Table1-1Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Medium-fertility(medium-mortality)projection(25)

Table1-2Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:High-fertility(medium-mortality)projection(26)

Table1-3Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Low-fertility(medium-mortality)projection(27)

Table1-4Meanageanddependencyratio(totalpopulation):Medium-,high-,andlow-fertility(medium-mortality)projections(28)

Table1-5Numberandrateofbirths,deathsandnaturalincrease(totalpopulation):Medium-fertility(medium-mortality)projection(29)

Table1-6Numberandrateofbirths,deathsandnaturalincrease(totalpopulation):High-fertility(medium-mortality)projection(30)

Table1-7Numberandrateofbirths,deathsandnaturalincrease(totalpopulation):Low-fertility(medium-mortality)projection310)

Figure1-1ActualandprojectedpopulationofJapan:Medium-,high-,andlow-fertility(medium-mortality)projections(32)

Figure1-2Trendsintheproportionofthepopulationaged65andover:Medium-,high-,andlow-fertility(medium-mortality)projections(33)

Figure1-3Trendsinthepopulationofmajorthreeagegroups:Medium-fertility(medium-mortality)projections(33)

Figure1-4Trendsintheproportionofmajorthreeagegroups:Medium-fertility(medium-mortality)projections(34)

Figure1-5Populationpyramid(totalpopulation):Threefertilityvariantprojectionswithamedium-mortalityassumption(34)

[ProjectionResultsforMedium-Fertility(High-andLow-Mortality)]

Table2-1Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Medium-fertility(high-mortality)projection(37)

Table2-2Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Medium-fertility(low-mortality)projection(38)

Table2-3Meanageanddependencyratio(totalpopulation):Medium-fertility(medium-,high-,andlow-mortality)projections(39)

Figure2-1ActualandprojectedpopulationofJapan:Medium-fertility(medium-,high,andlow-mortality)projections(40)

Figure2-2Trendsintheproportionofthepopulationaged65andover:Medium-fertility(medium-,high,andlow-mortality)projections(40)

[ComparisonofProjectionResultswithDifferentAssumptions]

Table3-1Totalpopulation:Medium-,high-,andlow-fertility(medium-,high-,andlow-mortality)projections(43)

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Table3-2Proportionofpopulationaged0-14(totalpopulation):Medium-,high-,andlow-fertility(medium-,high-,andlow-mortality)projections(44)

Table3-3Proportionofpopulationaged15-64(totalpopulation):Medium-,high-,andlow-fertility(medium-,high-,andlow-mortality)projections(45)

Table3-4Proportionofpopulationaged65andover(totalpopulation):Medium-,high-,andlow-fertility(medium-,high-,andlow-mortality)projections(46)

[Assumptions]

Table4-1Trendsofthetotalfertilityrate:Medium-,high-,andlow-fertility(medium-mortality)projectionsTable4-2Trendsoflifeexpectancyatbirth(50)

Table4-3Age-specificnetinternationalmigrationratesbysexforJapanese(51)

Table4-4Numberofnetmigrantsofnon-Japaneseoriginbysex(52)

Table4-5Agedistributionofnetmigrantsofnon-Japaneseoriginbysex(52)

Figure4-1Trendsofthetotalfertilityrate:Medium-,high-,andlow-fertility(medium-mortality)projections(53)

Figure4-2Trendsoflifeexpectancyatbirth:Medium-,high-,andlow-fertility(medium-mortality)projections(53)

Figure4-3Age-specificnetinternationalmigrationratesbysexforJapanese(54)

Figure4-4Numberofnetmigrantsofnon-Japaneseorigin(bothsexes)(54)

Figure4-5Agedistributionsofnetmigrantsofnon-Japaneseoriginbysex(54)

[Long-rangeAuxiliaryProjections]

SupplementTable1Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Medium-fertility(medium-mortality)projection(57)

SupplementTable2Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:High-fertility(medium-mortality)projection(58)

SupplementTable3Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Low-fertility(medium-mortality)projection(59)

SupplementTable4Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Medium-fertility(high-mortality)projection(60)

SupplementTable5Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Medium-fertility(low-mortality)projection(61)

SupplementTable6Totalpopulation:Medium-,high-,andlow-fertility(medium-,high-,andlow-mortality)projections(62)

[ProjectionsfortheJapanesePopulationandFertilityAssumptions]

JapanesePopulationProjectionsTable1Japanesepopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover),andagecomposition:Medium-fertility(medium-mortality)projection(65)

JapanesePopulationProjectionsTable2Numberandrateofbirths,deathsandnaturalincrease(Japanesepopulation):Medium-fertility(medium-mortality)projection(66)

JapanesePopulationProjectionsFigure1ActualandprojectedJapanesepopulation:Medium-,high-,andlow-fertility(medium-mortality)projections(67)

JapanesePopulationProjectionsFigure2Trendsintheproportionofthepopulationaged65andover:Medium-,high-,andlow-fertility(medium-mortality)projections(67)

JapanesePopulationProjectionsFigure3Trendsinthepopulationofmajorthreeagegroups:Medium-fertility(medium-mortality)projections(68)

JapanesePopulationProjectionsFigure4Trendsintheproportionofmajorthreeagegroups:Medium-fertility(medium-mortality)projections(68)

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JapanesePopulationProjectionsFigure5Populationpyramid(Japanesepopulation):Threefertilityvariantprojectionswithamedium-mortalityassumption(69)

[ConditionalPopulationProjections]

Conditionalprojectiontable1Totalpopulation:Totalfertilityrate(2070)1.00,1.20,1.40,1.60,1.80,2.00,2.20(73)

Conditionalprojectiontable2Populationaged65andover(totalpopulation):Totalfertilityrate(2070)1.00,1.20,1.40,1.60,1.80,2.00,2.20(74)

Conditionalprojectiontable3Totalpopulation：InternationalMigrationConditions(2040)Numberofnet

migrantsofnon-Japaneseorigin,0,50,000,69,000,100,000,250,000,500,000,750,000,1,000,000(75)

Conditionalprojectiontable4Proportionofpopulationaged65andover：InternationalMigrationConditions(2040)Numberofnetmigrantsofnon-Japaneseorigin,0,50,000,69,000,100,000,250,000,500,000,

750,000,1,000,000(76)

[Appendix]

AppendixTable1Totalpopulation,populationbythemajorthreeagegroups(under15,15-64,and65andover)andagecomposition:1950-2020(79)

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PopulationProjectionsforJapan(2023revision):2021to2070

KeyMessages

Japan’spopulationisprojectedtodecreaseby30%,andthepopulationaged65andovertomakeupabout40%ofthepopulationby2070.Whiletheprojectedfuturetotalfertilityratesarelowerthanthoseinthepreviousrevisionreleasedin2017,thepaceofpopulationdeclinewouldslowslightlyduetoanincreaseinlifeexpectancyandariseinnetmigrationofnon-Japanesenationalsinthisrevision.

TheNationalInstituteofPopulationandSocialSecurityResearch(IPSS)publishedthe2023revisionofpopulationprojectionsforJapan,usingthePopulationCensusofJapanin2020asthebasepopulation.Theseprojectionscalculatethepopulationsizeandage/sexcompositionatthenationallevelbasedonassumptionsabouttrendsinfertility,mortality,andinternationalmigration.TheseprojectionscoverallresidentsofJapan.

[Methodology]

Thecohort-componentmethodemployingrecenttrendsoffertility,mortality,andinternationalmigrationwasusedtoobtainthefuturepopulationbysexandagefrom2021to2070.

Basedontherecentdemographictrendsupto2020,thesizeandtheagestructureofthepopulationasofOctober1foreachyearareprojectedupto2070.Consideringuncertaintiesinfuturedemographics,weproducednine“basicscenarios”withvaryingassumptionsaboutthefuturecourseoffertilityandmortality(medium-,high-,andlow-variantforeach).

Moreover,weproducedthreeadditionalprojections:“long-rangepopulationprojections”(2071-2120),“populationprojectionsfortheJapanesenationals”,and“conditionalpopulationprojections”.

[AssumptionsandResults]

Comparedtothepreviousprojectionsin2017,the2023revisionexpectsafurtherdeclineinfertility,aslightincreaseinlifeexpectancy,andariseinnetmigration.

・ReflectingtheslumpthathadalreadystartedbeforetheCOVID-19pandemic,thetotalfertilityrateinthemedium-fertilityscenarioisprojectedtobe1.36in2070,showingadeclinefrom1.44in2065inthe2017revision.Furthermore,intheshortterm,thefertilityratewillremainlowmainlyduetothedropinmarriagesduringtheCOVID-19pandemic(Table4-1,Figure4-1).

・Lifeexpectancyisexpectedtoincreasefrom81.58yearsformenand87.72yearsforwomenin2020to85.89yearsformenand91.94yearsforwomenin2070(medium-mortalityscenario).Futurelifeexpectancyisprojectedtobeslightlyhigherthanthatinthe2017revision(84.95yearsformenand91.35yearsforwomenin2065)(Table4-2,Figure4-2).

・ThenegativenetmigrationfortheJapanesewasweakened,andthistrendwasincorporatedintotheassumption.Meanwhile,basedontherecentincreaseinthenumberofinternationalmigrantsduringthepre-pandemicperiod,thenetmigrationassumptionwasraisedtogrowfrom69,000peryear(2035)inthe2017revisionto164,000(2040)inthisprojection(Tables4-3-4-5,Figures4-3-4-5).

In50years,thetotalpopulationisprojectedtodecreasetonearly70%ofthecurrentlevel,andthepopulationaged65andovertoaccountforabout40%(medium-fertility/medium-mortalityscenario).

・ThetotalpopulationofJapan,126.15millioncountedinthePopulationCensusin2020,isprojectedtodecreaseto87millionin2070(downto69.0%ofthepopulationin2020)(medium-fertility/medium-mortalityscenario)(Table1-1,Figure1-1).

・Thepercentageofthepopulationaged65andoverisexpectedtorisefrom28.6%in2020to38.7%in2070(Table1-1,Figure1-2).

・Whilethepreviousrevisionprojectedthetotalpopulationin2065tobe88.08million,thefigureisexpectedtobe91.59millioninthisprojection.Moreover,accordingtotheassumptionofthisrevision,thetotalpopulation

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willfallbelow100millionin2056,adelayof3years(2053)fromthepreviousprojection.Thepaceofpopulationdeclineisexpectedtoslowdownslightly,mainlyduetotheincreaseininternationalmigration(Table1-1).

・Theprojectedpercentageofthepopulationaged65andoverin2065remainsunchangedfromthepreviousrevisionat38.4%.However,thesizeofthepopulationaged65andoverpeaksat39.53millionin2043inthisrevision,slightlymorethan39.35millionin2042inthepreviousrevision(Table1-1).

Projectionsbasedonhighandlow-fertilityscenariosandprojectionslimitedtotheJapanesepopulation

・In2070,thetotalpopulationandthepercentageofthepopulationaged65andoverareexpectedtobe95.49millionand35.3%,respectively,inthehigh-fertilityscenario(TFRof1.64).Inthemeantime,basedonthelow-fertilityscenario(TFRof1.13),thefiguresare80.24millionand42.0%,respectively(Tables1-2-1-3,Figures1-1-1-2).

・Inthemedium-fertility/medium-mortalityscenario,theJapanesepopulationin2070isprojectedtobe77.61million,andthepercentageofthepopulationaged65andoveris40.9%(Table1,Figures1-2).

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10

Highfertilityvariantprojection

MediumfertilityvariantprojectionLowfertilityvariantprojection

Males100Females

70Aged65-74

Aged65+

Aged75+80

Aged0-14

Aged15-6440

ActualandprojectedpopulationofJapan:Medium-,high-,andlow-fertility(medium-mortality)

projections

14000(

12000(

Fertiliy

assumptio

10000(

High-variart

80000

60000

40000

20000

Actualprojected

19701980199020002010202020302040205020602070

year

Populationpyramid:Threefertilityvariantprojectionswithamedium-mortalityassumption

(1)2020

90

60

50

30

20

10

0

13012011010090807060504030201000102030405060708090100110120130

(tenthousand)

(2)2070

Males

Females

100

90

80

70

60

50

40

30

20

0

13012011010090807060504030201000102030405060708090100110120130

(tenthousand)

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PopulationProjectionsforJapan(2023revision)

TheNationalInstituteofPopulationandSocialSecurityResearchhasconductedanewnationalpopulationprojectionexerciseandpublishedtheresultsas“PopulationProjectionsforJapan(2023revision).”Theprojectionsarebasedonthelatestdatafromthebasiccompletetabulationonpopulationfromthe2020populationcensusandthefinalcountforthevitalstatisticsfromthesameyear,aswellastheresultsofthe16thJapanesenationalfertilitysurvey,whichwasdelayedforoneyearduetotheoutbreakofCOVID-19.Thisisthe16threleaseofPopulationProjectionsforJapanbytheInstitute,includingthosefromtheperiodoftheformerInstituteofPopulationProblems.Thefollowingisasummaryoftheprojections.

Thetablesshowingthemainresultsoftheseprojectionshavebeenomittedfromthissummary.PleaserefertothewebsiteoftheNationalInstituteofPopulationandSocialSecurityResearchforthesetables.

IOverviewofthePopulationProjectionsforJapan

ThePopulationProjectionsforJapanprojectfuturepopulationsize,agecomposition,andotherdemographicstructuretrendsfortheentirecountrybasedonassumptionsaboutfuturebirths,deaths,andinternationalmigrationlevels.Consideringthatfuturetrendsinbirths,deaths,andotherfactorsaresubjecttouncertainty,theseprojectionssetassumptionsbasedonmultipleprojectionlevels,conductestimatesforanumberofdifferentpatterns,andprovideawell-definedrangeoffuturepopulationtrendsbasedontheseresults.

ThesubjectoftheprojectionsisthetotalpopulationpermanentlyresidinginJapan,includingnon-Japanese.Thisisthesameasthesubjectofthepopulationcensus.Theperiodfortheprojectionsbeginswiththe2020

populationcensusandcontinuesfrom2021to2070,projectingthepopulationasofOctober1foreachyear.Populationestimatesupto2120(asofOctober1foreachyear)arealsocalculatedandincludedforreference.

Themethodofprojectionisbasedoninternationallystandardizeddemographicmethods.First,assumptionsaresetforthefactorsofpopulationchange:births,deaths,andinternationalmigration,bysexandageintheformofprojectionsintothefutureforactualtrendsinstatisticalindicatorsrelatedtoeachofthosefactorsusingmathematicalmodels,etc.Next,thefuturepopulationbysexandageisprojectedaccordingtothecohortcomponentmethod,whichappliestheseassumptionstothebasepopulationtoestimatethepopulationoneyearlater.(Forfurtherdetails,referto“IIISummaryoftheMethodUsedforPopulationProjections.”)

IISummaryoftheProjectionResults

ThePopulationProjectionsforJapansetthreeassumptions(medium,high,andlow)forfuturefertilityandmortalitytrendsandcombinetheseassumptionsintoatotalofnineprojections(thesearereferredtoasthe“baseprojection”).Hereafter,thereportfirstdescribesasummaryoftheresultsforthethreeprojectionscombiningthethreeassumptionsonfertilitywiththemedium-mortalityassumption.Thisisfollowedbyasummaryoftheresultscombiningthethreeassumptionsonfertilitywiththehigh-mortalityandthelow-mortalityassumptions.Inthefollowingdescriptions,eachprojectionisreferredtobythecombinationofitsrespectivefertilityandmortalityassumptions,e.g.“medium-fertility(medium-mortality)projection”.

ProjectionResultsforMedium-,High-,andLow-Fertility(Medium-Mortality)

1.TrendsinTotalPopulation

Accordingtothe2020populationcensus,whichservesasthebaseyearforthesepopulationprojections,thetotalpopulationofJapanwas126.15million.Basedontheresultsofthemedium-fertilityprojection,thetotal

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populationhasenteredalong-termprocessofpopulationdecline.After108.8millionin2045,thepopulationisexpectedtofallbelow100millionto99.65millionin2056andto87millionin2070.(Table1-1,Figure1-1).

Basedonthehigh-fertilityprojection,thetotalpopulationisexpectedtofallbelow100millionin2064to99.53millionandto95.49millionin2070(Table1-2,Figure1-1).

Meanwhile,basedonthelow-fertilityprojection,thepopulationisexpectedtofallbelow100millionin2052anddeclineto80.24millionin2070(Table1-3,Figure1-1).

Comparedtothelastmedium-fertilityprojectionfortheyear2065,thetotalpopulationfigureincreasedby3.51million,from88.08millionto91.59million.Theyearinwhichthepopulationfallsbelow100millionshiftedfrom2053to2056,threeyearslaterthaninthepreviousprojection.

2.TrendsintheSizeandCompositionofthePopulationbytheMajorThreeAgeGroups

(1)Trendsinthe0-14yearsoldpopulationanditscomposition

ThenumberofbirthsinJapanhasdeclinedfrom2.09millionin1973to810,000in2020.Asaresult,the0-14yearsoldpopulation(totalpopulationincludingnon-Japanese)hasalsodecreasedfrom27millionintheearly1980sto15.03millioninthe2020populationcensus.

The0-14yearsoldpopulation,alsoreferredtoastheyoung-agepopulation,declinestothe14millionlevelin2021,accordingtotheresultsofthemedium-fertilityprojection(Table1-1,Figure1-3).Thenumberisexpectedtocontinuetodecline,fallingbelow10millionin2053andreachinganestimated7.97millionby2070.

Lookingattrendsforthe0-14yearsoldpopulationunderdifferentbirthrateassumptions,evenunderthehigh-fertilityprojection,the0-14yearsoldpopulationisheadedonadownwardtrend,fallingto11.15millionin2070(Table1-2).Thelow-fertilityprojectionindicatesamorerapiddeclineinthe0-14yearsoldpopulation,fallingbelow10millionin2037andreaching5.69millionin2070(Table1-3).

Examiningthisdeclineinthe0-14yearsoldpopulationintermsoftheratiotothetotalpopulation(thepercentageofthe0-14yearsoldpopulation),accordingtothemedium-fertilityprojection,thefigurewillcontinuetodeclinefrom11.9%in2020to10.9%in2026,10.0%in2034,and9.2%in2070(Table1-1,Figure1-4).

Thehigh-fertilityprojectionshowsasomewhatslowerdeclineinthepercentageofthe0-14yearsoldpopulation,fallingto11.1%in2029,followedby11.7%in2070(Table1-2).Incontrast,thelow-fertilityprojectionshowsarapiddeclineinthepercentageofthe0-14yearsoldpopulation,droppingto10.1%in2028and8.0%in2056,followedby7.1%in2070(Table1-3).

(2)Trendsinthe15-64yearsoldpopulationanditscomposition

The15-64yearsoldpopulation,alsoreferredtoastheworking-agepopulation,increasedconsistentlyinthepostwarperiod,reachingitspeakof87.26millioninthe1995populationcensus,buthasenteredaphaseofdeclinesincethen,fallingto75.09millionaccordingtothe2020populationcensus.

Thefuture15-64yearsoldpopulationisexpectedtofallbelow70million,60million,and50millionin2032,2043,and2062,respectively,downto45.35millionin2070,accordingtothemedium-fertilityprojection(Table1-1,Figure1-3).

Thetrendsforthe15-64yearsoldpopulationinthehigh-andlow-fertilityprojectionsarethesameasthoseinthemedium-fertilityprojectionuntil2035.After2035,thehigh-fertilityprojectionshowsaslightlyslowerpaceofdeclineinthe15-64yearsoldpopulation,fallingbelow60millionin2044andreaching50.67millionin2070(Table1-2).Accordingtothelow-fertilityprojection,the15-64yearsoldpopulationdeclinesatafasterpace,fallingbelow50millionin2057andreaching40.87millionin2070(Table1-3).

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Regardingtheratioofthe15-64yearsoldpopulationtothetotalpopulation(thepercentageofthe15-64yearsoldpopulation),accordingtothemedium-fertilityprojection,itwillcontinuetodeclinefrom59.5%asof2020tobelow55%in2041and52.1%in2070(Table1-1,Figure1-4).

Inthehigh-fertilityprojection,thepercentageofthe15-64yearsoldpopulationhasshownadeclinesincethebeginningoftheprojectionperiod,reaching53.1%in2070,whichis1.0percentagepointhigherthantheresultofthemedium-fertilityprojection.

Inthelow-fertilityprojection,thepercentageofthe15-64yearsoldpopulationwillbe50.9%in2070,about1.0percentagepointlowerthanthemedium-fertilityprojection.

(3)Trendsinthepopulationaged65andoveranditscomposition

Thetrendsinthepopulationaged65andover(numberofelderly)willbethesameforthethreeassumptionsonfertilitythroughoutthe50-yearprojectionperiodwhentheassumptiononmortalityisthesame.Inotherwords,thepopulationaged65andoverwillincreasefrom36.03millionasof2020to37.04millionby2032(Table1-1,Table1-2,Table1-3,Figure1-3).Thepaceofincreasewillacceleratethereafter,peakingat39.53millionin2043,afterthesecondbabyboomgeneration(bornbetween1971and1974)movesintothepopulationaged65andover.Subsequently,thenumberwillbegintodecline,reaching33.67millionin2070.

Lookingattheratioofthepopulationaged65andovertothetotalpopulation(thepercentageofthepopulationaged65andover),28.6%,or1outofevery3.5persons,isaged65andoverasof2020.Accordingtothemedium-fertilityprojection,thepercentageofthepopulationaged65andoverwillbe33.9%,or1outofevery3persons,in2038,and38.7%,or1outofevery2.6persons,in2070(Table1-1,Figure1-2).

Inthehigh-fertilityprojection,33.7%,or1outofevery3persons,willbeage65andoverin2039,and35.3%,or1outofevery2.8persons,in2070(Table1-2,Figure1-2).Also,inthelow-fertilityprojection,33.8%,or1outofevery3persons,willbeage65andoverin2037,and42.0%,or1outofevery2.4persons,in2070(Table1-3,Figure1-2).

Regardingthedifferenceinthedegreeofpopulationagingduetochangesinfuturefertilitylevels,acomparisonofthepercentageofthepopulationaged65andoverbetweenthehigh-andlow-fertilityprojectionsshowsadifferenceof2.0percentagepointsin2045:37.2%inthelow-fertilityprojectionand35.2%inthehigh-fertilityprojection.Thisdifferencewillwidenfurtherinsubsequentyears,to6.7percentagepointsin2070,with42.0%inthelow-fertilityprojectionand35.3%inthehigh-fertilityprojection(Figure1-2).

Asnotedabove,thepopulationaged65andoverwillpeakin2043anddeclinethereafter.However,thepercentageofthepopulationaged65andoverwillcontinuetoriseoverthenext50yearsunderboththemedium-andlow-fertilityassumptions.Thisisbecausethedeclinesinthe0-14and15-64yearsoldpopulationsarerelativelylargerthanthoseinthepopulationaged65andover.

Comparedtothelastmedium-fertilityprojectionfortheyear2065,thepopulationaged65andoverincreasedby1.32