曼昆中級(jí)宏觀經(jīng)濟(jì)學(xué)第五版第二章

LearningobjectivesInthischapter,youwilllearnabouthowwedefineandmeasure:GrossDomesticProduct(GDP)theConsumerPriceIndex(CPI)theUnemploymentRateGrossDomesticProductTwodefinitions:1.Totalexpenditureondomestically-producedfinalgoodsandservices2.

Totalincomeearnedbydomestically-locatedfactorsofproductionWhyexpenditure=incomeIneverytransaction,

thebuyer’sexpenditurebecomestheseller’sincome.Thus,thesumofallexpenditureequals

thesumofallincome.TheCircularFlowValueaddeddefinition:Afirm’svalueaddedisthevalueofitsoutput minusthevalueoftheintermediategoodsthefirmusedtoproducethatoutputExercise:Afarmergrowsabushelofwheat

andsellsittoamillerfor￥1.00.Themillerturnsthewheatintoflour

andsellsittoabakerfor￥3.00.Thebakerusestheflourtomakealoafof

breadandsellsittoanengineerfor￥6.00.Theengineereatsthebread.ComputevalueaddedateachstageofproductionGDPExerciseAnswerFarmer: ￥1 Miller: ￥3-￥1=￥2Baker: ￥6-￥3=￥3TotalGDP: ￥6TotalGDPisthesumofvalueadded,orthevalueofthefinalgood.TheMeasurementofGDPGDPmeasurestwothingsatonce:ThetotalincomeofeveryoneintheeconomyThetotalexpenditureontheeconomy’soutputofgoodsandservices.GrossDomesticProduct:Themarketvalue

ofall

final

goodsandservices

produced

withinacountry

inagivenperiodoftime.TheMeasurementofGDP“TheMarketValue…”MarketpricesareusedAddtogethermanydifferentitems(apples,shoes,lawyerfees,tuitions,etc.)“…ofAll…”Inclusions:allitemsproducedandsoldlegallyinthemarket.Exclusions:illegalgoodsorservicesoritemsthatarenotsoldinmarkets.TheMeasurementofGDP“…Final…”AharddrivesoldtoDellisanintermediategood

notincludedinGDP;AharddrivesoldtometoenlargethestorageofmyDelllaptopisafinalgoodcountedintoGDP.ThevalueofaharddriveisalreadyincludedaspartofthevalueofaDellPC.Seagate’sunsoldharddrives?Asaninventory,countedasfinalgoodsaswell.TheMeasurementofGDP“…GoodsandServices…”Bothtangiblegoods(food,clothing,cars)andintangiblegoods(haircuts,housecleaning,doctorvisits)Aswellasthosegoodsandservicesprovidedbythegovernment.“…Produced…”UsedcarsalesnotcountedintoGDP.Financialtransactionsnotincluded.TheMeasurementofGDP“…WithinaCountry…”WithinthegeographicbordersMyteachinginEmoryiscountedaspartofU.S.GDPnotChina’sCocaCola’s2/3ofannualsalesarecountedasGDPofcountriesotherthanU.S.“…InaGivenPeriodofTime”AyearoraquarterReportedinannualbasisandseasonallyadjustedTheComponentsofGDPGDP(Y)isthesumofthefollowing:Consumption(C)Investment(I)GovernmentPurchases(G)NetExports(NX)Y=C+I+G+NXConsumption(C)durablegoods

e.g.cars,homeappliancesnon-durablegoods

e.g.food,clothingservices

e.g.drycleaning,airtravel.Thevalueofallgoodsandservicesboughtbyhouseholdwiththeexceptionofpurchasesofnewhousing.U.S.Consumption,2001Investment(I)def1:spendingon[thefactorofproduction]capital.def2:spendingongoodsandservicesforfutureuse.Includes:businessfixedinvestment

spendingonplantandequipmentthatfirmswillusetoproduceothergoodsandservicesresidentialfixedinvestment

spendingonhousingunitsbyconsumersandlandlordsinventoryinvestment

thechangeinthevalueofallfirms’inventoriesU.S.Investment,2001Investmentvs.CapitalCapitalisoneofthefactorsofproduction.

Atanygivenmoment,theeconomyhasacertainoverallstockofcapital.Investmentisspendingonnewcapital.Investmentvs.CapitalExample(assumesnodepreciation):1/1/2002:

economyhas￥500bworthofcapitalduring2002:

investment=￥37b1/1/2003:

economywillhave￥537bworthofcapitalStocksvs.Flows

stock flow aperson’swealth aperson’ssaving #ofpeoplewith #ofnewcollege

collegedegrees graduates thegovt.debt thegovt.budgetdeficitFlowStockMoreexamples:Governmentspending(G)Gincludesallgovernmentspendingongoodsandservices.Gexcludestransferpayments (e.g.unemploymentinsurancepayments)

theyarenotmadeinexchangeforcurrentlyproducedgoodsandservices.Governmentspending,2001Netexports(NX=EX-IM)Thevalueoftotalexports(EX)minusthevalueoftotalimports(IM)China’snetexports

source:IFSAnimportantidentityY=C+I+G+NXwhere

Y=GDP=thevalueoftotaloutput

C+I+G+NX=aggregateexpenditureMeasureofNationalIncomeWhomakestheexpenditure

TypeofexpenditureHouseholds Consumption(Food, clothes,haircuts,newcars)Businessfirms Investment(Newfactories andequipment,newhouses, increasesininventorystocks)Governments Governmentpurchases (Newschoolbuildings,new militaryhardware,salariesof soldiersandgovernmentofficials)Foreignsectors Netexports,orexports minusimports(exported manufacturedgoods,legaland financialservicesprovidedby domesticresidentstoforeigners)USGDPandItsComponents(2004)Consumption70%GovernmentPurchases19%NetExports-5%Investment16%CompositionofChina’sGDP

source:PennWorldTable6.2CompositionofChina’sGDPCompositionofUSGDPAquestionforyou:Supposeafirmproduces$10millionworthoffinalgoodsbutonlysells$9millionworth.Doesthisviolatethe

expenditure=outputidentity?Whyoutput=expenditureUnsoldoutputgoesintoinventory,

andiscountedas“inventoryinvestment”… …whethertheinventorybuildupwasintentionalornot.Ineffect,weareassumingthat

firmspurchasetheirunsoldoutput.HowwouldeachofthefollowingtransactionaffecttheGDPofChina?TheChinesegovernmentpays￥1billioninsalariesforgovernmentworkersfightingforthesnowcrisis.TheChinesegovernmentpays￥1billiontouninsuredseniorcitizenstocovertheirmedicalexpenses.TheChinesegovernmentpaysLenovo￥1billionfornewlyproducedlaptops.TheChinesegovernmentpays￥1billiontoSaudiArabiaforcrudeoiltoaddtoChina’sofficialoilreserve.Foreachofthefollowingtransactions,statetheeffectbothonChina’sGDPandonthefourcomponentsofaggregateexpenditureYourmother-in-lawbuysanewcarfromCheryAuto.Yourmother-in-lawbuysanewVolvoimportedfromSweden.Yourmother-in-law’scarrentalbusinessbuysanewBuickfromShanghaiGM.Chinesegovernmentbuysanew,domesticallyproducedPolofortheuseofyourmother-in-law,whoistheambassadortoJapan.GDP:

AnimportantandversatileconceptWehavenowseenthatGDPmeasurestotalincometotaloutputtotalexpenditurethesumofvalue-addedatallstages

intheproductionoffinalgoodsGNPvs.GDPGrossNationalProduct(GNP):

totalincomeearnedbythenation’sfactorsofproduction,regardlessofwherelocatedGrossDomesticProduct(GDP):

totalincomeearnedbydomestically-locatedfactorsofproduction,regardlessofnationality (GNP–GDP)=(factorpaymentsfromabroad)

–(factorpaymentstoabroad)DiscussionQuestion:WhatexplainswhyGNPdiffersfromGDPforsomeofthefollowingcountries?(GNP–GDP)asapercentageofGDP

forselectedcountries,1997.CrosscountrycomparisonofGNP/GDPRealvs.NominalGDPGDPisthevalueofallfinalgoodsandservicesproduced.NominalGDPmeasuresthesevaluesusingcurrentprices.RealGDPmeasurethesevaluesusingthepricesofabaseyear.RealGDPcontrolsforinflationChangesinnominalGDPcanbedueto:ChangesinpricesChangesinquantitiesofoutputproducedChangesinrealGDPcanonlybeduetochangesinquantities,BecauserealGDPisconstructedusingconstantbase-yearprices.PracticeproblemComputenominalGDPin2002and2003ComputerealGDPineachyearusing2002asthebaseyear.20062007PQPQgoodA$110$215goodB$103$154AnswerstopracticeproblemNominalGDPmultiplyPs&Qsfromsameyear

2006:

2007:RealGDPmultiplyeachyear’sQsby2002Ps

2006:

2007:Soinrealterms,GDPdidnotriseasmuchasitwouldseemfromnominalterms. U.S.Real&NominalGDP,1967-2001GDPDeflatorTheinflationrateisthepercentageincreaseintheoveralllevelofprices.Onemeasureofthepricelevelis

theGDPDeflator,definedasUnderstandingtheGDPdeflatorExamplewith3goodsForgoodi=1,2,3 Pit=themarketpriceofgoodiinmontht Qit=thequantityofgoodiproducedinmontht NGDPt=NominalGDPinmontht RGDPt=RealGDPinmonthtUnderstandingtheGDPdeflatorTheGDPdeflatorisaweightedaverageofprices.Theweightoneachpricereflects

thatgood’srelativeimportanceinGDP.Notethattheweightschangeovertime.Anotherexample,

GDPfortheRepublicofAntaiRepublicofAntaiproducesthreemajorgoods,“Bachelors”,“MBAs”,and“Ph.D.s”,everyyear.Theproductionandpricesofthesethreegoodsin2005,2006,and2007areasfollows:

Bachelors

MBAs

Ph.D.s QuantityPrice QuantityPrice QuantityPrice2005 200 ￥45,000 150 ￥95,000 20 ￥80,0002006 350 ￥50,000 300 ￥120,000 50 ￥95,0002007 500 ￥75,000 200 ￥145,000 90 ￥99,000FindNominalGDPandRealGDP(baseyear2005)foreachyear.Calculatetheannualgrowthinrealproductionof“Bachelors”,“MBAs”,and“Ph.D.s”overyears.CalculatetheannualgrowthinNominalandRealGDP.FindtheGDPdeflatorsofAntaiRepublicoveryears.WorkingwithpercentagechangesEX: Ifyourhourlywagerises5%

andyouwork7%morehours,

thenyourwageincomerisesapproximately12%.USEFULTRICK#1ForanyvariablesXandY, thepercentagechangein(X

Y

)

thepercentagechangeinX

+thepercentagechangeinYWorkingwithpercentagechangesEX: GDPdeflator=100

NGDP/RGDP. IfNGDPrises9%andRGDPrises4%,

thentheinflationrateisapproximately5%.USEFULTRICK#2 thepercentagechangein(X/Y

)

thepercentagechangeinX

thepercentagechangeinYChain-weightedRealGDPOvertime,relativepriceschange,sothebaseyearshouldbeupdatedperiodically.Inessence,“chain-weightedRealGDP”updatesthebaseyeareveryyear.Thismakeschain-weightedGDPmoreaccuratethanconstant-priceGDP.Butthetwomeasuresarehighlycorrelated,andconstant-pricerealGDPiseasiertocompute……sowe’llusuallyuseconstant-pricerealGDP.GDPandEconomicWell-beingthebestsinglemeasureoftheeconomicwell-beingofasociety.GDPperpersontellsustheincomeandexpenditureoftheaveragepersonintheeconomy.HigherGDPperpersonindicatesahigherstandardofliving.notaperfectmeasureofthehappinessorqualityoflife,however.GDPandtheQualityofLifeGDPandEconomicWell-beingSomethingsthatcontributetowell-beingarenotincludedinGDP.Thevalueofleisure.Thevalueofacleanenvironment.Thevalueofalmostallactivitythattakesplaceoutsideofmarkets,suchasthevalueofthetimeparentsspendwiththeirchildrenandthevalueofvolunteerwork.ConsumerPriceIndex(CPI)AmeasureoftheoveralllevelofpricesPublishedbytheBureauofLaborStatistics(BLS)Usedtotrackchangesinthetypicalhousehold’scostoflivingadjustmanycontractsforinflationallowcomparisonsofdollarfiguresfromdifferentyearsHowtheBLSconstructstheCPISurveyconsumerstodeterminecompositionofthetypicalconsumer’s“basket”ofgoods.Everymonth,collectdataonpricesofallitemsinthebasket;computecostofbasketCPIinanymonthequalsThecompositionoftheCPI’s“basket”食品33.6煙酒及用品14.4衣著9家庭設(shè)備及服務(wù)6.2醫(yī)療保健及個(gè)人用品9.4交通及通信9.3娛樂(lè)教育文化服務(wù)4.5居住13.6中國(guó)CPI的構(gòu)成及其權(quán)重%鄭京平在05年4月國(guó)家統(tǒng)計(jì)局新聞發(fā)布會(huì)上公布的資料上海社會(huì)科學(xué)院在上海徐匯區(qū)進(jìn)行的一項(xiàng)調(diào)查發(fā)現(xiàn)，子女教育支出占所有家庭花費(fèi)的22%—41%之間。UnderstandingtheCPIExamplewith3goodsForgoodi=1,2,3 Ci=theamountofgoodiintheCPI’sbasket Pit=thepriceofgoodiinmontht Et=thecostoftheCPIbasketinmontht Eb=costofthebasketinthebaseperiodUnderstandingtheCPITheCPIisaweightedaverageofprices.Theweightoneachpricereflects

thatgood’srelativeimportanceintheCPI’sbasket.Notethattheweightsremainfixedovertime.Reasonswhy

theCPImayoverstateinflationSubstitutionbias:TheCPIusesfixedweights,

soitcannotreflectconsumers’abilitytosubstitutetowardgoodswhoserelativepriceshavefallen.Introductionofnewgoods:Theintroductionofnewgoodsmakesconsumersbetteroffand,ineffect,increasestherealvalueofthedollar.ButitdoesnotreducetheCPI,becausetheCPIusesfixedweights.Unmeasuredchangesinquality:

Qualityimprovementsincreasethevalueofthedollar,butareoftennotfullymeasured.TheCPI’sbiasTheBoskinPanel’s“bestestimate”:

TheCPIoverstatesthetrueincreaseinthecostoflivingby1.1%peryear.Result:theBLShasrefinedthewayitcalculatestheCPItoreducethebias.ItisnowbelievedthattheCPI’sbiasisslightlylessthan1%peryear.

CPIvs.GDPdeflatorpricesofcapitalgoodsincludedinGDPdeflator(ifproduceddomestically)excludedfromCPIpricesofimportedconsumergoodsincludedinCPIexcludedfromGDPdeflatorthebasketofgoodsCPI:fixedGDPdeflator:changeseveryyearTwomeasuresofinflation16

14

12

10

8

6

4

2

0

-2Percentagechange194819531958196319681973Year19781983198819931998CPIGDPdeflatorMeasuringUnemployment:

Categoriesofthepopulationemployed

workingatapaidjobunemployed

notemployedbutlookingforajoblaborforce

theamountoflaboravailableforproducinggoodsandservices;allemployedplusunemployedpersonsnotinthelaborforce

notemployed,notlookingforwork.IdentifyingUnemploymentHaveyouspentmostofthepreviousweekworkingatapaidjob?YES:EmployedNO:nextquestionAreyouontemporarylayoff,lookingforajob,orwaitingforthestartdateofanewjob.YES:UnemployedNO:Notinthelaborforce(students,homemakers,retirees)Laborforce=Employed+UnemployedWhoisemployed?Anexercise王寶強(qiáng)works10hoursaschefinalocalrestaurantandattendsnightschoolat安泰.Heprefersafulltimejobthough.周杰倫losthisjobatWal-Mart.Sincethenhehasbeentryingtofindanotherone.崔永元isanMBAfrom安泰andnowworksfulltimeasdishwasher.Hedislikeshisjobandhasappliedforjobswithseveralfirms.Hewillquitcurrentjobassoonashegetsanoffer.陳冠希istakingabreakfromhiscurrentjobasmagicianfor10years.Hedecidestohaveavocationinthenext24months.MeasurementofUnemploymentSourcesofmis-measurementofunemploymentrate:Frequentmovementsintoandoutofthelaborforce.NewcollegegraduatesRetireeschangemindtoworkagain,etc.Peoplecallingthemselves“unemployed”toqualifyforgovernmentassistance,yetnotactivelytryingtofindwork,arecountedasunemployedbutactuallynotinlaborforce.Discouragedworkers,notcountedinlaborforcebutactuallyinvoluntaryunemployment.Twoimportantlaborforceconceptsunemploymentrate

percentageofthelaborforcethatisunemployedlaborforceparticipationrate

thefractionoftheadultpopulationthat‘participates’inthelaborforceComputinglaborforcestatisticsU.S.adultpopulationbygroup,April2002 Numberemployed = 134.0million Numberunemployed = 8.6million Adultpopulation = 213.5millionApplyingourdefinitionsdata:E=134.0,U=8.6,POP=213.5laborforce

L==1