If you ever wanted a quick way to estimate how many years it’ll take for your investments to double, take 72 and divide it by the interest rate. In this episode, we explore how this a great way to think about the power of compound interest. If you’re early in your career, it may encourage you to set aside more money now. And if you’re close to retirement, it can be reassuring to know your investment could double in the next 7-10 years.