It now anticipates a population of 9.7 billion in 2050, and 11.2 billion – and still rising – by 2100, because fertility rates in several countries have fallen more slowly than expected (in some, notably Egypt and Algeria, fertility has actually risen since 2005). While the combined population of East and Southeast Asia, the Americas, and Europe is projected to rise just 12% by 2050 and then start falling, sub-Saharan Africa’s population could rise from 960 million today to 2.1 billion by 2050 and almost four billion by 2100.