According to a USA TODAY Money story:
According to research out of George Washington University, only one-third of Americans actually get how compounding works, leaving most of the public in the dark. And you really don’t need a math brain to grasp the concept. You just need to run some numbers to see how compounding can help or destroy your finances.
Let me demonstrate:
Save $100 a month for thirty-years, earn 5% annually and you will have $ 83,673, but only $36,100 of that amount is the money you saved. The balance is due to the power of compounding interest. Interest on interest added to your savings.