Enter the annual interest rate into the calculator to determine the number of years it will take for an investment to double.

## Rule Of 115 Formula

The following formula is used to calculate the number of years it will take for an investment to double using the Rule of 115.

Y = 115 / r

Variables:

- Y is the number of years it will take for the investment to double
- r is the annual interest rate (percentage)

To calculate the number of years it will take for an investment to double, divide 115 by the annual interest rate. The result is approximately the number of years it will take for the investment to double.

## What is a Rule Of 115?

The Rule of 115 is a quick and simple way to estimate when an investment will double given a specific interest rate. It is used when the interest rate is compounded annually and the rate is above 6%. To use the rule, you divide 115 by the annual interest rate. The result is approximately the number of years it will take for the investment to double.

## How to Calculate Rule Of 115?

The following steps outline how to calculate the Rule of 115.

- First, determine the annual interest rate (r) as a percentage.
- Next, divide 115 by the annual interest rate (r) to calculate the number of years (Y) it will take for the investment to double.
- Finally, calculate the Rule of 115.
- After inserting the variables and calculating the result, check your answer with the calculator above.

**Example Problem:**

Use the following variables as an example problem to test your knowledge.

Annual interest rate (r) = 5%

Number of years (Y) = ?