| | Knox City, TX | Haskell, TX | United States |
| Population | 948 | 3,013 | 329,725,481 |
| Female Population | 45.3% | 44.1% | 50.5% |
| Male Population | 54.8% | 55.9% | 49.5% |
| Median Age | 44.1 | 41.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,131 | 3,307 | 309,327,143 |
| Population - 2000 | 1,219 | 3,106 | 285,036,114 |
| Population - 1990 | 1,440 | 3,362 | 251,960,433 |
| Pop. 2000 to Now | -8.1% | 3.2% | 15.6% |
| Pop. 1990 to Now | -22.2% | -4.7% | 30.8% |
| space4 | | | |
| Population Density | 1,138.1 | 837.4 | 93.4 |
| Land Area | 0.8 | 3.6 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Knox City, TX | Haskell, TX | United States |
| Age 0 to 4 | 5.0% | 1.9% | 5.9% |
| Age 5 to 9 | 6.1% | 4.1% | 6.1% |
| Age 10 to 14 | 5.5% | 6.5% | 6.6% |
| Age 15 to 17 | 6.3% | 3.8% | 3.9% |
| Age 18 to 20 | 4.9% | 9.5% | 4.0% |
| Age 21 to 24 | 5.7% | 3.6% | 5.2% |
| Age 25 to 34 | 9.9% | 12.5% | 13.8% |
| Age 35 to 44 | 8.7% | 13.7% | 12.9% |
| Age 45 to 54 | 10.2% | 9.4% | 12.6% |
| Age 55 to 59 | 6.1% | 6.2% | 6.7% |
| Age 60 to 64 | 10.3% | 8.2% | 6.3% |
| Age 65 to 74 | 13.3% | 10.5% | 9.6% |
| Age 75 to 84 | 6.2% | 7.0% | 4.5% |
| Age 85 and over | 1.8% | 3.1% | 1.9% |
| space1 | | | |
| Race | | | |
| | Knox City, TX | Haskell, TX | United States |
| White | 56.6% | 62.6% | 59.4% |
| Black | 2.5% | 6.0% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 1.4% | 0.4% | 3.2% |
| Hispanic | 39.5% | 31.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Knox City, TX | Haskell, TX | United States |
| Married Population | 45.3% | 44.4% | 49.8% |
| Currently Married | 42.7% | 40.9% | 48.0% |
| Married but Separated | 2.5% | 3.5% | 1.8% |
| Single Population | 54.7% | 55.6% | 50.2% |
| Never Married | 29.5% | 38.8% | 33.8% |
| Divorced | 8.0% | 10.2% | 10.8% |
| Widowed | 17.3% | 6.6% | 5.6% |
| space5 | | | |
| Household Size | 2.54 | 2.54 | 2.60 |
| Households | 354 | 1,069 | 124,010,992 |
| Family Households | 204 | 695 | 80,755,759 |
| Married couple, w/children | 35.3% | 14.1% | 30.5% |
| Married couple, no children | 42.2% | 54.8% | 42.9% |
| Non Family Households | 150 | 374 | 43,255,233 |
| Single householder, w/children | 3.9% | 24.7% | 15.8% |
| Single householder, no children | 18.6% | 6.3% | 10.8% |