Interview, Fireside Chat
Why the world’s population is heading for collapse
- Rich countries and increasingly lower-income nations face fertility rates below the 2.1 replacement level, leaving only central Asia and sub-Saharan Africa with above-replacement rates for the remaining third of the global population.
- The UN baseline projects the global population will continue growing for several decades to a peak of approximately 10 billion in the 2080s, contingent on current trends; however, if declines persist for five, 15, or 25 additional years, this peak could arrive around 2070, 2060, or closer to the mid-century mark, respectively.
- South Korea may lose roughly one-fifth of its population by mid-century if current fertility declines continue, while the global population is expected to reach a peak position over the next few decades for the first time since the Black Death.
- Historical trends where richer women had more children are reversing due to a global convergence of income levels and lifestyle desires, which is pulling aggregate fertility rates down from the lower end of the income distribution.
- In the US, fertility declines since 1990 are largely driven by mothers under 19 having fewer children due to reduced teen pregnancy, though college-educated women now have slightly more children than some lower-income groups.
- College-educated US women are delaying first births to ages 28 to 30, while significant fertility drops remain concentrated among younger, less educated demographics where childbearing trade-offs are more complex.
- While a potential correction in fertility rates may occur as women have children later, assuming a global rise in rates due to mean reversion is considered naive given the persistent, cross-cultural nature of the decline.