What will one investment (lump sum) be worth or accumulate to in the future? If you know the amount you want to invest, the interest rate you can earn and the number of periods, you can discover the future amount. If you invest $1,000 today and you earn 5% interest for 20 years what will your investment be worth? Go to table 1 go down 20 periods and go across to 5% and you will find 2.65330. $1,000 X 2.65330 gives you $2,653.30. 1. Your question. Same information, but you can earn 10%. What will the investment be worth? 2. If you invest $10,000 today for 5 years at 15%, what will it be worth?