| Year | Total | Density (D=N/S) |
| 1790 | 3,920,214 | 4.5 |
| 1800 | 5,308,484 | 6.1 |
| 1810 | 7,239,881 | 4.3 |
| 1820 | 9,638,433 | 5.5 |
| 1830 | 12,866,020 | 7.4 |
| 1840 | 17,069,453 | 9.8 |
| 1850 | 23,191,876 | 7.9 |
| 1860 | 31,443,321 | 10.6 |
| 1870 | 38,558,371 | 13.0 |
| 1880 | 59,155,783 | 16.9 |
| 1890 | 62,947,714 | 21.2 |
| 1900 | 75,994,575 | 25.6 |
| 1910 | 96,973,266 | 31 |
| 1920 | 105,710,620 | 35.5 |
| 1930 | 123,710,046 | 41.2 |
| 1940 | 131,669,275 | 44.2 |
| 1950 | 150,697,361 | 50.7 |
| 1960 | 179,323,175 | 53.6* inc. Alaska and Hawaii |
| 1970 | 203,346,298 | 57.5 |
| 1980 | 226,504,827 | 62.7 |
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