| | Rockdale, TX | Hamilton, TX | United States |
| Population | 5,378 | 2,885 | 329,725,481 |
| Female Population | 54.1% | 49.8% | 50.5% |
| Male Population | 46.0% | 50.2% | 49.5% |
| Median Age | 37.9 | 38.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 5,493 | 3,088 | 309,327,143 |
| Population - 2000 | 5,439 | 2,977 | 285,036,114 |
| Population - 1990 | 5,235 | 2,937 | 251,960,433 |
| Pop. 2000 to Now | 0.2% | 1.6% | 15.6% |
| Pop. 1990 to Now | 4.1% | 3.0% | 30.8% |
| space4 | | | |
| Population Density | 1,342.5 | 832.1 | 93.4 |
| Land Area | 4.0 | 3.5 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Rockdale, TX | Hamilton, TX | United States |
| Age 0 to 4 | 6.0% | 3.9% | 5.9% |
| Age 5 to 9 | 6.8% | 6.7% | 6.1% |
| Age 10 to 14 | 7.0% | 8.0% | 6.6% |
| Age 15 to 17 | 3.4% | 3.2% | 3.9% |
| Age 18 to 20 | 8.7% | 9.6% | 4.0% |
| Age 21 to 24 | 3.5% | 2.4% | 5.2% |
| Age 25 to 34 | 12.2% | 9.2% | 13.8% |
| Age 35 to 44 | 9.6% | 12.7% | 12.9% |
| Age 45 to 54 | 14.4% | 9.4% | 12.6% |
| Age 55 to 59 | 5.8% | 7.1% | 6.7% |
| Age 60 to 64 | 7.2% | 5.0% | 6.3% |
| Age 65 to 74 | 9.2% | 12.5% | 9.6% |
| Age 75 to 84 | 4.5% | 5.0% | 4.5% |
| Age 85 and over | 1.8% | 5.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | Rockdale, TX | Hamilton, TX | United States |
| White | 53.7% | 77.9% | 59.4% |
| Black | 10.7% | 0.3% | 12.2% |
| Asian | 0.8% | 0.0% | 5.6% |
| Native American | 0.3% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.1% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.7% | 4.1% | 3.2% |
| Hispanic | 33.8% | 17.5% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Rockdale, TX | Hamilton, TX | United States |
| Married Population | 50.5% | 43.1% | 49.8% |
| Currently Married | 48.3% | 41.6% | 48.0% |
| Married but Separated | 2.2% | 1.5% | 1.8% |
| Single Population | 49.5% | 56.9% | 50.2% |
| Never Married | 31.2% | 33.1% | 33.8% |
| Divorced | 12.9% | 12.4% | 10.8% |
| Widowed | 5.4% | 11.3% | 5.6% |
| space5 | | | |
| Household Size | 2.62 | 2.91 | 2.60 |
| Households | 2,018 | 943 | 124,010,992 |
| Family Households | 1,131 | 551 | 80,755,759 |
| Married couple, w/children | 38.2% | 22.9% | 30.5% |
| Married couple, no children | 44.8% | 37.6% | 42.9% |
| Non Family Households | 887 | 392 | 43,255,233 |
| Single householder, w/children | 7.0% | 27.9% | 15.8% |
| Single householder, no children | 10.0% | 11.6% | 10.8% |