U.S. population at 10 year intervals, 1790 – 1980 (USA Bureau of Census)
Year     Value
1790   3929214
1800   5308483
1810   7239881
1820   9638453
1830  12860702
1840  17063353
1850  23191876
1860  31443321
1870  38558371
1880  50189209
1890  62979766
1900  76212168
1910  92228496
1920 106021537
1930 123202624
1940 132164569
1950 151325798
1960 179323175
1970 203302031
1980 226545805
1990 248709873