World fertility rate by country. The US has a Total Fertility Rate of 2.0 - meaning that there is zero to negative population growth without immigration.

Except for Africa, most countries have a TFR below 2.1, which is necessary to maintain a current population.

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World historical TFR (1950–2015) UN, medium variant, 2010 rev. [2]

Years TFR
1950–1955 4.95
1955–1960 4.89
1960–1965 4.91
1965–1970 4.85
1970–1975 4.45
1975–1980 3.84
1980–1985 3.59
1985–1990 3.39
1990–1995 3.04
1995–2000 2.79
2000–2005 2.62
2005–2010 2.52
2010–2015 2.36