You are planning to save for retirement over the next 20 yea
You are planning to save for retirement over the next 20 years. To do this, you will invest $800 a month in a stock account and $500 a month in a bond account. The return of the stock account is expected to be 9 percent, and the bond account will pay 4 percent. When you retire, you will combine your money into an account with a 7 percent return. Required: How much can you withdraw each month from your account assuming a 20-year withdrawal period?
Solution
(1) In the first step we shall compute the future value of monthly Investments.
FVIFA = [ (1+r)n - 1 ] / r
Here n = 20 Years * 12 = 240
r = return / 12
at 9% return ......... [ (1.00759)240 - 1 ] / 0.0075 = 667.886870
at 4% return ...........[ (1.0.00333333)240 - 1 ] / 0.00333333 = 366.774626
Future value = 800 * 667.886870 + 500 * 366.774626 = 717696.81
(2) In this second and last step we calculate monthly withdrawing from this fund invested at 7 %
For this compute the PVIFA ......... Present value of Interest factor annuity
= [ 1 - (1+r)-n ] / r
= [ 1 - (1.00583333)-240 ] / 0.00583333 = 128.98
Monthly withdrawal = Fund / PVIFA = 717696.81 / 129.98 = 5521.59 ........ Final answer

