Suppose you have $100 in a savings account earning 2 percent interest a year. After five years, how much would you have?
You'll have more than $102 at the end of five years because your interest will compound over time. In other words, you earn interest on the money you save and on the interest your savings earned in prior years. Here's how the math works. A savings account with $100 and a 2 percent annual interest rate would earn $2 in interest for an ending balance of $102 by the end of the first year. Applying the same 2 percent interest rate, the $102 would earn $2.04 in the second year for an ending balance of $104.04 at the end of that year. Continuing in this same pattern, the savings account would grow to $110.41 by the end of the fifth year.