Suppose you plan to retiring 40 years from now. After retiring, you believe you will live 20 more years and will require $100,000 per year. let's assume for now that all of your investing will be in a mutual fund that returns 9% annually. You also have no initial value in the account. What is the annual investment required to meet retirement needs? Assume that the withdrawals are at the beginning of each period, since we will spend it as we go. PV = FV 1/(1+r) N PV = present value FV = future value r = rate of return n = number of periods