The UN projects that while Europe stagnates, Sub-Saharan Africa’s population will explode from ~one billion today to almost four billion souls by the end of the century. Steve Sailer famously calls this the World’s Most Important Graph.
However, the African continent is a land of marked contrasts. Which African regions are going to be especially “important” in this respect?
As usual thanks to Twitter demographer Cicerone, I discovered that something called the DHS Program has been polling almost all African countries (as well as most of the developing world) on their fertility preferences. (See previous post for global details).
At a glance, it seems that within S.S.-Africa itself, the demographic explosion in the next 100 years is going to be particularly concentrated in the west and center of the continent, while the east and south will grow more moderately. In particular, the higher quality African countries – Kenya (3.6); Rwanda (3.4); Ethiopia (5.3) – or, at least, its non-Somali areas – tend to have lower desired fertility, while the champion prospective breeders are the inland Muslim states of Chad (8.2) and Niger (9.2 ideal number of children in 2012, up from 8.2 in 1992; no wonder projections have its population rising to almost 200 million by 2100, up tenfold relative to today).
The highest populated African state at the present time, Nigeria, sets the ideal number of children at 6.1 as of 2018 (no change since 1990, when it was at 5.8). If you look at the map closely, you will see major differences between the Christian south (clustering at 4-5 children) and the Muslim north (clustering at 7-9 children).
There is a pretty good correlation between ideal and realized fertility (e.g. r=0.63 in Europe), so the above numbers should be broadly predictive of future trends.
The one bright spot is that S.S.-Africans are not immune to the demographic transition. Industrialized South Africa sets the ideal number of children at 2.6, while its real TFR is now at 2.4 children per woman.