UN: Half of world’s population growth is likely to occur in Africa

Story highlights

A new report predicts the world's population will hit a staggering 9.8 billion by 2050

Fertility rates are dropping globally but remain high in Africa

Nine countries will contribute to more than half of the world's population growth, and five are on the African continent

CNN  — 

Nigeria will overtake the United States to become the third-most populous country in the world by 2050, according to a United Nations report.

Currently the seventh-most populous country in the world, the West African nation is projected to surpass the 300 million people mark by 2050, according to The World Population Prospects 2017.

The report predicted that the world population will hit a staggering 9.8 billion by 2050, and forecasted that over half of the expected growth between 2017 and 2050 is likely to occur in Africa.

Here are five African countries that will contribute the most to the world’s population growth.

Nigeria

A view of multi-story buildings in Lagos, Nigeria's commercial capital.

With an estimated population of more than 180 million people, Nigeria experienced annual population growth of about 2.7% between 2010 and 2015, according to the UN.

Nigeria's population in numbers

Current population: 187 million (2016) Population by 2050: over 300 millionLargest city: Lagos- between 17.5 and 21 million residents

High fertility rates, high infant mortality rates and the cultural value of large families have all been cited as factors driving Nigeria’s population boom.

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