Suppose that the average annual growth rate that each country achieved over the period 2005–2015 continues indefinitely into the future. Starting from 2015, use the Rule of 70 to calculate, where possible, the year in which a country will have doubled its real GDP per capita. Round the year to nearest whole number.

Check the explanation

Explanation:

Using Rule of 70, Doubling period = 70 / Annual growth rate

(i) Doubling period, Argentina = 70 / 3.11 = 22.5 years ~ 23 years

Argentina doubles its GDP by 2038 (= 2015 + 23).

(ii) Doubling period, Ghana = 70 / 4.45 = 15.7 years ~ 16 years

Ghana doubles its GDP by 2031 (= 2015 + 16).

(iii) Doubling period, South Korea = 70 / 3.02 = 23.2 years ~ 23 years

South Korea doubles its GDP by 2038 (= 2015 + 23).