题目解释:一个投资项目,初始是140000,税前现金流如下,如果税率是40%,问税后的payback Period是多少>

考点:payback Period的计算   关键词:after-tax payback period

解题思路:根据payback period的计算公式计算

After 3.4 years, only $127,200 of the initial $140,000 investment will have been recouped. That is calculated as $36,000 + $36,000 + +$36,000 + (.4 × $48,000), since $36,000 is the annual after-tax cash flow for each of the first 3 years ($60,000 × .6) and $48,000 is the annual after-tax cash flow for the fourth year ($80,000 × .6).
After 1.5 years, only $54,000 of the initial $140,000 investment will have been recouped. That is calculated as $36,000 + (.5 × $36,000), since $36,000 is the annual after-tax cash flow for each of the first 3 years ($60,000 × .6).
After 2.3 years, only $82,800 of the initial $140,000 investment will have been recouped. That is calculated as $36,000 + $36,000 + (.3 × $36,000), since $36,000 is the annual after-tax cash flow for each of the first 3 years ($60,000 × .6).
The after-tax cash flows and cumulative cash flows of the project, which are used to calculate the payback period, are as follows: Before-Tax Cash Flow After-Tax Cumulative Cash Flow Cash Flow Year 0 $(140,000) $(140,000) $(140,000) Year 1 60,000 × .60 = 36,000 (104,000) Year 2 60,000 × .60 = 36,000 (68,000) Year 3 60,000 × .60 = 36,000 (32,000) Year 4 80,000 × .60 = 48,000 16,000 Year 5 80,000 × .60 = 48,000 64,000 The payback period is the number of the final year in which the projected cash flow is negative (Year 3), plus a fraction consisting of: Numerator: The positive value of the negative cumulative cash flow amount from the final negative year ($32,000) Denominator: Cash flow for the following year ($48,000). Thus, the payback period is 3 + (32,000/48,000), or 3.67 years, which rounded is 3.7 years.