## Rule of 72

The **rule of 72** is a popular formula used to roughly estimate how long it will
take for your investments to double in time assuming a constant rate of return.

The formula is extremely simple! Just take the number 72 and divide it by the interest rate that you hope to earn from your investments.

We'll now ask you a few questions about your personal finances to show you that, even with modest initial savings, you can accumulate a significant amount of wealth.

## How much can you start with?

## Doubling Time

With the expected annual return rate, the **rule of 72** lets you estimate that your
investments will double every ** years**.

Now let's watch what happens when we take advantage of compounding interest...