A NEW statistical analysis shows that the world population could reach nearly 11 billion people by the end of the century, according to a U.N. report.
That's about 800 million, or 8%, more than the previous projection of 10.1 billion issued in 2011.
The projected rise is mostly due to fertility in Africa, where the U.N. had expected birth rates to decline more quickly than they have.
"The fertility decline in Africa has slowed down or stalled to a larger extent than we previously predicted, and as a result, the African population will go up," said Adrian Raftery, a University of Washington professor of statistics and sociology.
The current population of Africa is about 1.1 billion and is now expected to reach 4.2 billion by 2100, nearly a fourfold increase.
The new U.N. estimates use statistical methods developed by Raftery and his colleagues at the University of Washington Center for Statistics & the Social Sciences. The group's improved fertility forecasting methods, combined with updated data collected by the U.N., were used to project the long-term consequences of the fertility change in Africa since the last population estimate two years ago.
New to this year's projection are finer-tuned statistics that anticipate the life expectancies of women and men across this century.
In other areas of the world, fewer major population changes are expected. Europe may see a small decline because of fertility remaining below the replacement level, and other nations around the globe may see modest increases due to longer life expectancies, Raftery said.
There's no end in sight for the increase in world population, he added, yet the topic has been trumped by other pressing global issues, including poverty and climate — both of which have ties to world population.
The global population passed 6 billion in 1999 and reached 7 billion in 2011
Editor's Note: Raftery discussed his projections in the "Feedstuffs in Focus" podcast at www.Feedstuffs.com.