We have issued a briefing on the contents and significance of the 2015 Revision of World Population Prospects recently published by the United Nations Department of Economic and Social Affairs (UNDESA).
The briefing focuses on the UNDESA’s projection that the population of the world will be approximately 11.2 billion at the end of the century. The projection is based on an assumption of considerable reductions in fertility rates in much of the world. Without such reductions the population would be about 13.3 billion, according to the Revision. The briefing echoes the UNDESA’s conclusion that the availability of family planning services must be increased across the globe.
Global variations in fertility are discussed in the briefing. The fertility rates of many developed countries — Japan and much of Europe — are already below the “replacement level” required to maintain the current population size, but 9 per cent of countries worldwide are classified as having “high fertility” — this means that an average woman gives birth to more than five children during the course of her lifetime. The regional variation in fertility rates — the majority of the “high fertility” nations are in Africa — is the reason for the significantly different distribution of the population predicted by the UNDESA.
The briefing reiterates the UNDESA’s findings on migration and ageing — both are expected to affect developed countries dramatically. In them 82 per cent of the population growth from now until 2050 is predicted to result from migration from other countries and average life expectancy is projected to increase by more than 10 years before 2100.