644M people have ever lived in the US — 53% are alive today
49 million children died before age 5; today that would be 3 million.
On the 250th anniversary of US independence, LessWrong user Novalis published a detailed demographic analysis estimating that 644 million people have ever lived in the United States since 1776. The figure includes the ~2.5 million people already alive at the founding, everyone born in the country since then (roughly 548 million), and immigrants (~73 million). A striking finding: 53% of all people who have ever lived in the US are alive today, reflecting modern longevity and continued population growth.
The estimate reconstructs births before national registration existed by applying decade-by-decade crude birth rates from demographer Michael R. Haines, separated for white and Black populations because birth rates differed significantly (e.g., 55 per 1,000 for whites in 1800 vs. ~58 for Blacks). The analysis also reveals that 49 million children (roughly 1 in 11 born in the US) died before age 5, a number that would drop to about 3 million under today's child mortality conditions. The post is a rigorous example of historical demography using limited data.
- 644 million people have ever lived in the US since 1776; 53% are still alive.
- 49 million children died before age 5 historically; modern rates would place that at ~3 million.
- Birth rate reconstruction used separate white/Black crude birth rates from Haines (1800-1900).
Why It Matters
Puts modern US demographics in historical perspective — most people who ever lived here are still alive.