| Year | Free | Slave | Total | % Slaves | Increase |
| 1790 | 3.2 | 0.7 | 3.9 | 21% | – |
| 1800 | 4.4 | 0.9 | 5.3 | 20% | 36% |
| 1810 | 6.0 | 1.2 | 7.2 | 20% | 36% |
| 1820 | 8.1 | 1.5 | 9.6 | 18% | 33% |
| 1830 | 10.9 | 2.0 | 12.9 | 18% | 34% |
| 1840 | 14.6 | 2.5 | 17.1 | 17% | 33% |
| 1850 | 20.0 | 3.2 | 23.2 | 16% | 36% |
| 1860 | 27.5 | 4.0 | 31.4 | 14% | 35% |
| 1870 | 38.6 | – | 38.6 | – | 23% |
| 1880 | 50.2 | – | 50.2 | – | 30% |
| 1890 | 63.0 | – | 63.0 | – | 25% |
| 1900 | 76.2 | – | 76.2 | – | 15% |
| 1910 | 92.2 | – | 92.2 | – | 27% |
| 1920 | 106.0 | – | 106.0 | – | 15% |
| 1930 | 127.0 | – | 127.0 | – | 16% |
| 1940 | 132.2 | – | 132.2 | – |