宏观经济学第七版答案曼昆

AnswerstoSelectedStudentGuideProblems**Notetoinstructors:Theanswerstomostofthedataquestionsweretakenfromthe2009EconomicReportofthePresident.Somedatafor2008weretakenfromtheBureauofEconomicAnalysisandDepartmentofLaborwebsites.ThedatamayberevisedinlaterpublicationsDataQuestions1.a.Thefollowing2008data,inbillionsofdollars,wereobtainedfromtheBureauofEconomicAnalysisWebsiteat–7(1)(2)GrossDomesticProduct$14,264.6EQUALSConsumption$10,057.9+Investment$1,993.5+GovernmentPurchasesofGoodsandServices$2,882.4+Exports$1,859.4–Imports$2,528.6b.GDP=$10,057.9+$1,993.5+$2,882.4–$669.2=$14,264.6(billion)2.a.Table2–8(1)(2)(3)(4)(5)%Change%ChangeinCPIfromGDPinGDPDeflatorfromYearCPIPrecedingYearDeflatorPrecedingYear2007207.34119.823.82.22008215.30122.50b.ImportedoilisnotpartofU.S.GDP.Therefore,itisnotincludedinthecalcula-tionoftheGDPdeflator,althoughitisincludedinthecalculationoftheCPIwhenitispurchasedbyconsumers.BecausetheUnitedStatesimports,ratherthanproduces,alargeportionoftheoilhouseholdsconsume,theoilpriceincreasehadagreatereffectontheCPIthanontheGDPdeflatorfrom2007to2008.203CHAPTER2TheDataofMacroeconomics3.a.Table2–9(1)(2)(3)(4)(5)%ChangeTotalU.S.inRealGDPRealGDPPopulationRealGDPperCapitafromYear($inbillions)(inmillions)perCapitaPrecedingDecade19785,015222.6$22,53022.219886,743245.0$27,52219.319989,067276.1$32,84016.7200811,652304.1$38,316b.U.S.realGDPpercapitagrewthefastestfrom1978to1988;itgrewtheslowestfrom1998to2008.4.a.andc.Table2–10(1)(2)(3)(4)(5)(6)(7)GDP%ChangeReal%ChangeNominal%ChangeYearDeflator(P)inPGDP(Y)inYGDP(Y)inPY($inbillions)($inbillions)2007119.8211,52413,8082.21.13.32008122.5011,65214,265b.3.3Problems10.a.Thecostsofexpectedinflationaretheshoeleathercostsofinflation,themenucostsofchangingprices,thecostofunindexedtaxes,thecostofgreatervariabilityinprices,andthecoststopeoplewhoreceiveincomesfixedinnominalterms(suchasprivatepensions)thatwerecontractedbeforetheinflationwasexpected.b.Althoughfederalincometaxesarenowindexedforinflation,taxesoncapitalgainsandinterestincomearenot.Consequently,ifinflationweretofallfrom2percentto0percentand,accordingtotheFishereffect,nominalinterestratesweretofallby2percentagepoints,theafter-taxrealreturntosavingandinvest-mentwouldincrease.c.3percent,assumingaconstantvelocityofmoneyd.Expectedinflationwouldfall;thenominalinterestratewouldfall;realmoneydemandwouldincreasebymorethanthe3-percentgrowthinoutput;realmoneybalanceswouldincreasebythesameamount;thepricelevelwouldfall;actualinflationwouldtemporarilybenegative.e.With0percentinflation,realwagescanfallonlyifnominalwagesdecline,andworkersvigorouslyresistreductionsinnominalwages.204AnswerstoSelectedStudentGuideProblemsCHAPTER4MoneyandInflationDataQuestions1.a.Table4–9(1)(2)(3)(4)(5)(6)(7)ConsumerPriceIndicesCPICPIAll%Medical%CPI%YearItemsChangeCareChangeEnergyChange197865.261.852.581.4124.370.01988118.3138.689.337.874.715.21998163.0242.1102.932.150.4130.02008215.3364.1236.7b.$8.49c.1978to1988d.1998to2008e.TheOPECoilshockin1979andthemostrecentshocksfrom2002to2005andin2008accountfortheincreaseintherelativepriceofoilduringthoseperiods.2.a.Table4–10(1)(2)(3)(4)(5)(6)(7)(8)Nominal%ChangeM1(Dec.)M2(Dec.)GDP($inGDPinGDP($in%Change($in%ChangeYearbillions)DeflatorDeflatorbillions)inM1billions)inM219782,29545.83571,36665.3120.4119.219885,10475.77872,99427.539.346.219988,74796.51,0964,37826.945.686.2200814,265122.51,5968,154b.Ifthelong-rungrowthrateofrealGDPis3percentperyear,orabout34percentperdecade,andvelocitywereconstant,thequantitytheorywouldpredictthatπ=%ChangeinM–34%perdecade.IfweuseM1asourmeasureofthemoneysupply,thesimplequantitytheorypre-dicts10-yearinflationratesof86.4percentfrom1978to1988;5.3percentfrom1988to1998,and11.6percentfrom1998to2008.c.UsingM1,thequantitytheoryisafairlygoodpredictorofinflationinthefirstandthirddecadesandapoorpredictorinthemiddledecade.d.IfweuseM2asourmeasureofthemoneysupply,thesimplequantitytheorypre-dicts10-yearinflationratesof85.2percent,12.2percent,and52.2percentforthethreedecades,respectively.Itisafairlygoodpredictorforthefirsttwodecades,butnotforthemostrecentdecade.3.a.VforM2in1978=1.68;VforM2in2008=1.75;obviously,M2velocityhasrisenabit,contrarytotheassumptionofthesimplequantitytheory,butnotmuch.Chapter4MoneyandInflation205b.VforM1in1978=6.43,VforM1in2008=8.94;M1velocityhasrisenalot,con-trarytotheassumptionofthesimplequantitytheory.c.Evenifvelocitychanges,MV=PYandthe%changeinM+%changeinVapproximatelyequalsthe%changeinP+%changeinY.Thus,ifbothvelocityandrealGDPchangesteadilyovertime,%changeinP=%changeinM+%changeinY–%changeinV,andanyincreaseinthemoneysupplywillbeaccom-paniedbyanequalincreaseinthepricelevel.Problems11.a.Ifthedeficitwereeliminated,publicsavingwouldrise.Iftaxeswerecut,inthelongrunprivatesavingwouldalsorise.Thus,nationalsavingwouldrise.b.Inaclosedeconomy,theScurveshiftsright(assavingincreases),therealrateofinterestfalls,andtheamountofinvestmentincreasesalthoughtheinvestmentcurvedoesnotshift:GraphforProblem11(b)206AnswerstoSelected