In human populations, replacement fertility is 2.1 children born per woman in a given population. Worldwide, the fertility rate has fallen from an average of 5 births per woman in 1950 to 2.3 births per woman in 2021.<ref>[https://www.unfpa.org/swp2023/too-few#:~:text=Since%201950%2C%20global%20average%20lifespans,births%20per%20woman%20in%202021. The Problem With Too Few], United Nations</ref> | In human populations, replacement fertility is 2.1 children born per woman in a given population. Worldwide, the fertility rate has fallen from an average of 5 births per woman in 1950 to 2.3 births per woman in 2021.<ref>[https://www.unfpa.org/swp2023/too-few#:~:text=Since%201950%2C%20global%20average%20lifespans,births%20per%20woman%20in%202021. The Problem With Too Few], United Nations</ref> |