Suppose I deposit $125 per month for 10 years into an account earning 6%. For the next 15 years I increase my deposits to $150 per month, then for the next 5 years after that I decrease to $80 per month. Find my total future value. Find the future value of an annuity of $500 per year at 9% for 20 years, assuming that the 12th and 15th annual payments are $850 instead of $500