WORLD GDP is growing at 4% per year, how long will it take for world GDP to double?

Your company’s revenue is growing at 10% per month, how long will it take for your company’s revenue to double?

There is a simple rule of thumb that you can use to figure out roughly how long it will take for something to double, given an expected growth rate.

### The Rule of 70

This rule of 70 can be described by the following equation:

If the world’s GDP is growing at 4% per year then global GDP will double in about 17 years.

If your company’s revenue is growing at 10% per month then revenues will double in about 7 months.