Originally Posted by

**mathceleb** Rambo,

Your initial deposit is at time 0. Beginning of Year. Your first deposit is at the end of year 1. Therefore, your initial deposit has already had 1 year of interest. So, when your last withdrawal at the end of year 8 occurs, your initial deposit at time 0 has already had 9 years to accumulate interest.

Also, you are accumulating in this problem, not discounting. Therefore, your series;

(1/(1.04)^1+1/(1.04)^2+1/(1.04)^3+1/(1.04)^4+1/(1.04)^5+1/(1.04)^6+1/(1.04)^7+1/(1.04)^8))= should not have 1/'s in it.

it should be:

(1.04)^1+(1.04)^2+(1.04)^3+(1.04)^4+(1.04)^5+(1.04 )^6+(1.04)^7

Since your withdrawals are at the end of the month, your time is 1 less.