basic immigration data

Updating the last two columns of the above table for recent decades

1990s net immigration was 6.4 per 1,000 population and accounted for 51.6% of population growth that decade

2000s 3.7 and 39.4

2010s 3.6 and 50.7

2020s (through 2024) 6.5 and 81.0

One thing to note is because the natural rate of increase (births minus deaths) has been slowing for decades now immigration will account for a larger part of population growth, simply because natural population growth has dropped so much.

Other countries (such as Japan) who have gone through this demographic transition without significant immigration have struggled with the economic and fiscal implications.

United States Population Growth

1960s 2.9 million per year
1970s 2.3
1980s 2.2
1990s 3.3
2000s 2.7
2010s 2.3
2020s 2.3

There is surprisingly little variation by decade. But the immigration share is growing due to a slower rate of natural increase.