What rule shows roughly how long it will take a nation to double its output at various growth rates?

Question

Quizplus · Accepted Answer

The rule of 70 is a widely used rule of thumb that estimates the number of years it will take for a nation's GDP to double, based on its annual growth rate. It states that if a nation's annual growth rate is x%, then it will take approximately 70/x years for the nation's GDP to double. For example, if a nation's annual growth rate is 4%, it will take approximately 70/4 = 17.5 years for its GDP to double. Therefore, the rule of 70 is the best choice for this question as it shows roughly how long it will take a nation to double its output at various growth rates.

What Rule Shows Roughly How Long It Will Take a Nation