Africa in 2100

By 2100, Africa's population is projected to reach 3.6 billion — making it by far the continent whose population is expected to grow the most by the next century. We wonder: How many African countries will have populations exceeding 100 million people by 2100?

A. One
B. Three
C. Five
D. 11

A. One is not correct.

Nigeria is the only country in Africa today whose population exceeds 100 million. According to the latest projections from the United Nations Population Division, Nigeria will retain its title as the most populous African nation. By 2100, its population will almost quintuple, rising from 158 million today to 730 million.

B. Three is not correct.

By 2100, three countries in Africa are projected to have populations greater than 200 million: Nigeria, Tanzania and the Democratic Republic of Congo (DRC). Tanzania will rank in second place, with 316 million people, and the DRC in third, with 212 million.

Tanzania will rise from sixth to second place by 2100 and see its population increase seven-fold, thanks to its consistently high fertility rate.

C. Five is not correct.

By 2050, Africa should have five countries with populations exceeding 100 million: Nigeria, DRC, Ethiopia, Tanzania and Egypt. The combined populations of just these five countries will be nearly a billion people, which is almost as many as live in all of Africa today.

The population growth rates vary significantly among countries. Zambia's population is set to explode from 13 million today to 140 million by 2100. Others will see more modest increases, with Ethiopia's rising from 83 million to 150 million by 2100 and Egypt's from 81 million to 123 million. Fertility rates are the key differentiating factor: Women in Zambia currently have, on average, six children, compared to between two and four children per woman in Ethiopia and Egypt.

D. 11 is correct.

Eleven African countries will have populations exceeding 100 million by 2100. In addition to the five that will reach this threshold by 2050 (Nigeria, DRC, Ethiopia, Tanzania and Egypt), six more will reach it by 2100: Uganda, Kenya, Zambia, Niger, Malawi and Sudan.

One notable absentee from the list is South Africa. Its population will barely change, rising from 50 million today to 54 million in 2100. This is due to its relatively low birth rate, combined with a population that has been ravaged by the HIV/AIDS epidemic.

Word count: 387