World Population to 2300
These long-range results are groundbreaking in two respects: they extend the time horizon to 2300 (previous long-range projections were to 2150) and they include country forecasts (previously, long-range projections were available by continent only). Such long-reaching projections are needed by environmental scientists, policy makers and others who assess the long-term implications of demographic trends.
According to the medium scenario of these projections (in which world fertility levels will eventually stabilize at around two children per woman), world population will rise from the current 6.3 billion persons to around 9 billion persons in 2300. However, even small variations in fertility levels will have enormous impacts in the long-term. As little as one-quarter of a child under the two-child norm, or one-quarter of a child above the norm, results in world population ranging from 2.3 billion (low variant) to 36.4 billion (high variant) in 2300. Another scenario (constant scenario), undertaken for the sake of illustration, finds that if fertility levels remain unchanged at today’s levels, world population would rise to 244 billion persons in 2150 and 134 trillion in 2300, clearly indicating that current levels of high fertility cannot continue indefinitely.