In 2012, the UN projected that Nigeria’s population would reach
914 million by the end of the 21st century.
The UN’s 2015 forecast of 752 million is 162 million people lower,
or about 20%.
This lowered projection is based on the country’s fertility rate
having fallen more rapidly than expected.
In the earlier population projection, the UN had expected Nigeria’s
fertility to remain above six children per woman during the early
decades of the 21st century.
The fertility rate has actually fallen to 5.74 in recent years.
This quicker initial drop in the fertility rate, small as it seems,
will have massive repercussions for Nigeria’s population total
— if it is sustained over the next 85 years.
Nigeria’s decline by 162 million people is equal to the population of
Bangladesh, currently the world’s eighth most populous country.
However, for the African continent as a whole, fertility rates are
expected to fall less quickly than previously estimated.
This means that Africa’s 2100 population is now forecast to reach
nearly 4.4 billion.
That total number is about 200 million more than the UN’s 2012
forecast, despite the simultaneous decline in Nigeria’s projected
population by 162 million.


Source: Data by UN Population Division.
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