1、Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall1 Chapter 5: Household Saving and Investment DecisionsObjectiveFinancial decisions in an uncertain world; Human capital, permanent income decisions over life cycle Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall2第五章

2、第五章: 居民戶的儲蓄和投資決策居民戶的儲蓄和投資決策Copyright Prentice Hall Inc. 2000. Author: Nick Bagley, bdellaSoft, Inc.學習目的學習目的不確定世界中的金融決策；不確定世界中的金融決策；生命周期中人力資本、生命周期中人力資本、永久性收入決策永久性收入決策Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall3Chapter 5 Contents 目錄目錄5.1 A Life-Cycle Model of Savings 生命周期儲蓄模型生命周

3、期儲蓄模型5.2 Taking Account of Social Security 考查社會保障考查社會保障5.3 Deferring Taxes through Voluntary Retirement Plans 通過自愿性退休計劃延遲支付稅收通過自愿性退休計劃延遲支付稅收5.4 Should you Invest in a Professional Degree? 你是否應當投資于一項專業(yè)學位？你是否應當投資于一項專業(yè)學位？5.5 Should you Buy or Rent? 你應當購買還是租賃？你應當購買還是租賃？Copyright 2009 Pearson Education,

4、Inc. Publishing as Prentice Hall4Objectives 學習目的學習目的 How much to save for retirement Whether to defer taxes or pay them now Whether to get a professional degree Whether to buy or rent an apartment 為退休儲蓄多少為退休儲蓄多少 延期納稅還是現(xiàn)在納稅延期納稅還是現(xiàn)在納稅 教育投資決策教育投資決策 購房還是租房購房還是租房Copyright 2009 Pearson Education, Inc. Pub

5、lishing as Prentice Hall55.1 A Life-Cycle Model of Saving 生命周期儲蓄模型生命周期儲蓄模型 Assume that you are currently 35 years old, expect to retire in 30 years at 65, and then live for 15 more years until 80 假定你現(xiàn)在假定你現(xiàn)在35歲，預計歲，預計30年后在年后在65歲退休，然后再歲退休，然后再生存生存15年直至年直至80歲歲 Your real labor income is $30,000/year unti

6、l age 65 你的實際收入在你的實際收入在65歲之前都保持每年歲之前都保持每年3萬美元萬美元 Interest rates exceed inflation by 3%/ year 利率每年比通貨膨脹率高利率每年比通貨膨脹率高3%，即實際利率，即實際利率3%Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall6How Much Should I Save and Consume?儲蓄多少？消費多少？儲蓄多少？消費多少？ Consider two approaches: Target replacement ra

7、te of pre-retirement income Maintain the same level of consumption spending 有兩種用來計算應當為退休儲蓄多少的方法：有兩種用來計算應當為退休儲蓄多少的方法： （1）以盯住退休前收入的置換率為目標；）以盯住退休前收入的置換率為目標； （2）以退休前后保持相同消費支出水平為目標）以退休前后保持相同消費支出水平為目標Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall71. Target replacement rate of pre-retir

8、ement income方法一：盯住退休前收入的置換率方法一：盯住退休前收入的置換率 First compute the retirement income. 首先首先計算退休收入計算退休收入 Many experts recommend a rate of 75% of the pre-retirement income. 許多專家建議許多專家建議置換率置換率等于退休前收入的等于退休前收入的75% $30,000*0.75 = $22,500/year 將退休基金看作普通年金計算現(xiàn)值，將退休基金看作普通年金計算現(xiàn)值，65歲時你需要歲時你需要 n=15, i = 3, PMT=22,500 -

9、 PV=268,604Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall8 Next compute how much you need to save each year 然后然后計算你每年需要儲蓄多少錢計算你每年需要儲蓄多少錢 n=15, i = 3, FV= 268,604 - PMT=5,646 To obtain $22,500 you need to save $5,646 per year 為了能在為了能在15年間每年取出年間每年取出22500美元的退休收益，你美元的退休收益，你需要在接下來的需要在

10、接下來的30年里年里(35-65歲歲)每年儲蓄每年儲蓄5646美元美元1. Target replacement rate of pre-retirement income方法一：盯住退休前收入的置換率方法一：盯住退休前收入的置換率Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall9Target replacement rate Conclusion盯住置換率方法的結(jié)論盯住置換率方法的結(jié)論 You will have noticed that your pre-retirement consumption is

11、$30,000 - $5,646 = $24,354; but the real retirement income is only $22,500 你會注意到，當你每年將你會注意到，當你每年將3萬美元中的萬美元中的5646美元儲美元儲蓄時，你退休前的消費是蓄時，你退休前的消費是34354美元，但是在退休美元，但是在退休后你的收入僅為后你的收入僅為22500美元。美元。即即70的置換率的置換率 The next method equates consumption 下一種方法使消費保持一致下一種方法使消費保持一致Copyright 2009 Pearson Education, Inc. Pu

12、blishing as Prentice Hall102.Maintain the same level of consumption spending方法方法2：保持消費支出的相同水平：保持消費支出的相同水平 Assume that your level of real consumption is C 假設(shè)你每年的消費水平是假設(shè)你每年的消費水平是C 在接下來在接下來 80-35=45 年間年間的消費總額現(xiàn)值，必須的消費總額現(xiàn)值，必須等于等于 65-35=30 年間年間退休收益的現(xiàn)值退休收益的現(xiàn)值 n = 30, i = 3, PMT = 3,000 - C=23,982 The savin

13、gs are then $30,000 - $23,982 = $6,018 因此，在退休前每年需要因此，在退休前每年需要儲蓄儲蓄6018美元美元Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall11Human Capital and Permanent Income人力資本和永久性收入人力資本和永久性收入 (P165) Human capital The present value of ones future labor income 人力資本：人力資本：未來勞動收入的現(xiàn)值未來勞動收入的現(xiàn)值 Permanen

14、t income The constant level of (real) consumption spending that has a present value equal to ones human capital 永久性收入：永久性收入：現(xiàn)值等于人力資本的不變消費支出水平現(xiàn)值等于人力資本的不變消費支出水平Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall12Labor Income and Consumption-500005000100001500020000250003000035000354045

15、50556065707580AgeReal $lab_incconsump收入收入 和和 消費消費Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall13Human Capital and Wealth-10000001000002000003000004000005000006000007000003545556575AgeReal $fundHumanCapCapital人力資本人力資本 和和 財富總量財富總量Copyright 2009 Pearson Education, Inc. Publishing a

16、s Prentice Hall14The Inter-temporal Budget Constraint 跨期預算約束跨期預算約束 P168011111TRttttttttCBYWiii Ct = consumption spending in year t 第第t t年的消費支出年的消費支出 Yt = labor income in year t 第第t t年的勞動收入年的勞動收入 i = interest rate 利率利率 R = number of years to retirement 直至退休的年數(shù)直至退休的年數(shù) T = number of years of remaining

17、life 生存年數(shù)生存年數(shù) W0 = initial wealth 初始財富價值初始財富價值 Bt = bequest made in year t 第第t t年的遺產(chǎn)年的遺產(chǎn)Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall15 Note that any lifetime consumption spending plan that satisfies your budget constraint (i.e. equation 5.2) is a feasible plan. (P169) 注意，任何滿足注意

18、，任何滿足預算約束（即方程預算約束（即方程5.2）的終生消費的終生消費支出計劃都是一項支出計劃都是一項可行計劃可行計劃The Inter-temporal Budget Constraint 跨期預算約束跨期預算約束Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall16Omars Life-Cycle Savings Plan 奧馬爾的生命周期儲蓄計劃奧馬爾的生命周期儲蓄計劃薪水薪水消費消費儲蓄儲蓄Copyright 2009 Pearson Education, Inc. Publishing as Prent

19、ice Hall175.2 Taking Account of Social Security 考察社會保障考察社會保障 In many countries the government obliges citizens to participate in a mandatory retirement income system called social security 在許多國家，政府要求公民參加一種被稱為在許多國家，政府要求公民參加一種被稱為社會保障社會保障的法定退休收入體系的法定退休收入體系 Contributors pay a tax during their working ye

20、ars, and in return qualify for a lifetime annuity in old age 人們在工作期間支付稅收，作為回報，在年老時有資人們在工作期間支付稅收，作為回報，在年老時有資格獲得終身年金格獲得終身年金Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall185.3 Deferring Taxes Through Voluntary Retirement Plans通過自愿性退休計劃延遲支付稅收通過自愿性退休計劃延遲支付稅收 Many countries encourage v

21、oluntary savings for retirement through provisions of the tax code. 許多國家通過提供稅收法律鼓勵為退休進行自愿儲蓄許多國家通過提供稅收法律鼓勵為退休進行自愿儲蓄 In the US employees are permitted to set up Individual Retirement Accounts (IRAs) that defer payment of taxes until retirement 在美國，員工被允許開設(shè)在美國，員工被允許開設(shè)個人退休帳戶（個人退休帳戶（IRAs），），該該賬戶可以延付稅收直至退休

22、賬戶可以延付稅收直至退休Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall19 These plans are called tax deferred rather than tax exempt because any amounts withdrawn from the plan are taxed at the time of withdrawal. 這些計劃之所以被稱為這些計劃之所以被稱為稅收延付稅收延付而非而非稅收豁免稅收豁免，是因，是因為任何從該計劃里取出的金額在提取時是要被征稅的為任何從該計劃里取出

23、的金額在提取時是要被征稅的5.3 Deferring Taxes Through Voluntary Retirement Plans通過自愿性退休計劃延遲支付稅收通過自愿性退休計劃延遲支付稅收Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall20The Advantage of Tax-Deferred Saving 稅收延付的優(yōu)勢稅收延付的優(yōu)勢Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall21 The tax-deterre

24、d savings plan provides a larger after-tax benefit 稅收延付型儲蓄計劃提供更大的稅后收益稅收延付型儲蓄計劃提供更大的稅后收益 When your tax rate remains unchanged, the benefit of deferral can be summarized in the rule: 當稅率保持不變時，稅收延付的利益可以概括為下述原則：當稅率保持不變時，稅收延付的利益可以概括為下述原則： Deferral earns you the pretax rate of return after tax. 延付使你在繳稅后還能

25、賺取稅前的收益率延付使你在繳稅后還能賺取稅前的收益率 (P174)5.3 Deferring Taxes Through Voluntary Retirement Plans通過自愿性退休計劃延遲支付稅收通過自愿性退休計劃延遲支付稅收Copyright 2009 Pearson Education, Inc. Publishing as Prentice Hall225.4 Should You Invest in a Professional Degree?你是否應當投資于一項專業(yè)學位？你是否應當投資于一項專業(yè)學位？ One purpose of additional schooling is to increase ones earning power 追求額外教育的一個目的是增強人們的賺錢能力追求額外教育的一個目的是增強人們的賺錢能力 Example: Getting a Graduate Degree 例如：獲得碩士學位例如：獲得碩士學位 Education may be viewed as an investment i