Implications of World Peak Population for Canada

Abstract

The last century witnessed the fastest population growth in human history, but this is now ending.2 Recent 2017 United Nations population projections assume that current fertility levels of 2.5 children per woman will decrease to 2.2 in 2050 and to a below-replacement level of 1.99 in 2100 (United Nations 2017).3 Estimated at 7.2 billion in 2013, the world’s population is expected to continue to grow, but at a much slower pace. It will eventually peak at slightly more than 11 billion in the 22nd century, and thereafter slowly decrease for the first time in several centuries. Under the United Nations’ low-fertility assumption, world population would peak even sooner, at 8.7 billion in about 2050 and decrease to 7.3 billion by 2100. Today’s current population is increasing by 1.1 per cent per year, compared to almost 2 per cent as recently as 1970–75. By the end of the current century, in 2095–2100, the United Nations expects world population growth to decrease to 0.1 per cent per year; however, peak population size does not occur in this century, according to the 2017 United Nations’ medium-fertility population projections. By 2095–2100, world population growth is small but still positive. If the United Nations’ rates are extrapolated beyond 2100, world population growth would decrease to zero in about 2110 (by linear extrapolation) or 2115 (by exponential extrapolation). Even though world fertility is projected to fall below replacement levels by 2100, the younger age distribution in some high-fertility countries provides “momentum” for continued population growth past 2100. Nevertheless, global world population growth is expected to cease by 2075 in all regions except Africa and Oceania.