Looks like every 10 years we have 20 to 30 million more people. And those are just the counted ones.
The data in the following table was provided by the U.S. Census Bureau.
Year Population Increase Percent
2000 281,421,906 32,712,033 13.2
1990 248,709,873 22,167,674 9.8
1980 226,542,199 23,240,168 11.4
1970 203,302,031 23,978,856 13.4
1960 179,323,175 27,997,377 18.5
1950 151,325,798 19,161,229 14.5
1940 132,164,569 8,961,945 7.3
1930 123,202,624 17,181,087 16.2
1920 106,021,537 13,793,041 15.0
1910 92,228,496 16,016,328 21.0
1900 76,212,168 13,232,402 21.0
1890 62,979,766 12,790,557 25.5
1880 50,189,209 11,630,838 30.2
1870 38,558,371 7,115,050 22.6
1860 31,443,321 8,251,445 35.6
1850 23,191,876 6,128,523 35.9
1840 17,063,353 4,202,651 32.7
1830 12,860,702 3,222,249 33.4
1820 9,638,453 2,298,572 33.1
1810 7,239,881 1,931,398 36.4
1800 5,308,483 1,379,269 35.1
1790 3,929,214 - -
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