
More than two-thirds of the world’s people now live in countries having too few children to hold their populations steady — a quiet reversal, crossed gradually over the past two decades, that demographers say will reshape economies, cities and old age within a single lifetime.
According to the UN Population Division's World Fertility 2024 report, 131 of the 237 countries and areas it tracks now have fertility below 2.1 births per woman, the rough level a population needs to replace itself without migration.














