| PEOPLE | Collinsville | Milliken | United States |
| Population | 25,579 | 5,610 | 308,035,306 |
| Pop. Density | 1,742 | 478 | 87 |
| Pop. Change | 2.59% | 88.60% | 8.07% |
| Median Age | 36.5 | 30.9 | 37.3 |
| Households | 10,927 | 1,861 | 116,716,292 |
| Household Size | 2.34 | 3.05 | 2.58 |
| Male Population | 48.87% | 49.79% | 49.27% |
| Female Population | 51.13% | 50.21% | 50.96% |
| Married Population | 49.09% | 55.44% | 47.02% |
| Single Population | 50.91% | 44.56% | 52.98% |
| ESTIMATED TOTAL POPULATION BY AGE | | | |
| Age 0 to 4 | 6.88% | 9.63% | 6.56% |
| Age 5 to 9 | 5.90% | 10.16% | 6.61% |
| Age 10 to 14 | 5.72% | 8.06% | 6.71% |
| Age 15 to 17 | 3.53% | 4.87% | 4.21% |
| Age 18 to 20 | 2.15% | 2.05% | 2.95% |
| Age 21 to 24 | 7.47% | 5.44% | 7.01% |
| Age 25 to 34 | 16.52% | 17.50% | 13.33% |
| Age 35 to 44 | 12.47% | 14.74% | 13.33% |
| Age 45 to 49 | 14.58% | 11.85% | 14.61% |
| Age 50 to 54 | 14.58% | 11.85% | 14.61% |
| Age 55 to 59 | 11.77% | 8.95% | 11.84% |
| Age 60 to 64 | 11.77% | 8.95% | 11.84% |
| Age 65 to 74 | 6.55% | 4.46% | 7.05% |
| Age 75 to 84 | 4.69% | 1.84% | 4.24% |
| Age 85 and over | 1.77% | 0.46% | 1.78% |
| RACE | | | |
| White | 85.34% | 82.10% | 72.41% |
| Black | 10.04% | 0.37% | 12.61% |
| Asian | 0.77% | 0.89% | 4.75% |
| American Indian | 0.23% | 0.50% | 0.95% |
| Other | 3.63% | 16.13% | 9.28% |
| Hispanic | 0.23% | 1.85% | 16.35% |
| Non-Hispanic | 99.77% | 98.15% | 83.65% |
| FAMILY | | | |
| Married, w/children | 26.29% | 42.94% | 30.42% |
| Married, no children | 44.03% | 38.59% | 42.46% |
| Single, w/children | 16.43% | 11.35% | 14.39% |
| Single, no children | 13.24% | 7.12% | 12.73% |
| Divorced | 12.59% | 9.74% | 10.62% |
| Separated | 1.98% | 4.90% | 4.97% |
| Widowed | 8.04% | 3.39% | 6.14% |
| Now Married | 48.37% | 54.77% | 46.32% |
| Never Married | 29.02% | 27.20% | 31.95% |
