金融学教学bodie2echapter05.pptx

-??-CycleModelofSavingAssumethatyouarecurrently35yearsold,expecttoretirein30yearsat65,eis$30,000/yearuntilage65Interestratesexceedinflationby3%/year文档分享4HowMuchShouldISaveandConsume?Considertwoapproaches:Targetreplacementrateofpre-eMaintainthesamelevelofconsumptionspending文档分享5Targetreplacementrateofpre-%ofthepre-e.$30,000*=$22,500/putethepresentvalueoftheretirementfundsasanregularannuityn=15,i=3,FV=0,PMT=-22,500->PV=268,604文档分享6Targetreplacementrateofpre-e(Cont.)putehowmuchyouneedtosaveeachyearn=30,i=3,PV=0,FV=-268,604->PMT=5,646Toobtainareal$22,500afterretirementyouneedtosave$5,-retirementconsumptionis$30,000-$5,646=24,354;eisonly$22,500Thenextmethodequatesconsumption文档分享8MaintainthesamelevelofconsumptionspendingAssumethatyourlevelofrealconsumptionisCThepresentvalueofconsumptionoverthenext45yearsmustequalthepresentvalueofearningsoverthenext30yearsUsingannuityformulawegotC=$23,982Thesavingsarethen$30,000-$23,982=$6,018Amoregeneralformula:eHumancapitalThepresentvalueofone’eTheconstantlevelof(real)consumptionspendingthathasapresentvalueequaltoone’shumancapital文档分享10