Map of population density in the U.S.

At the moment, about 328 million people are living in the U.S, a nation that’s 9.84 million sq km (3.53 million square miles). But during the country’s history, these numbers haven’t stayed fixed.

Animated map of population density in the U.S. (1790–2010)

The animated map of population density, made using Jonathan Schroeder’s county-level decadal estimates. Populations for intermediate years was interpolated by cubic splines to log-density; essentially, that means that it assumes a smooth change in the rate of growth for each county over time.

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