| PEOPLE | Springfield | Naperville | United States |
| Population | 30,484 | 141,853 | 308,035,306 |
| Pop. Density | 3,869 | 3,659 | 87 |
| Pop. Change | 25.14% | 9.36% | 8.07% |
| Median Age | 38.2 | 37.7 | 37.3 |
| Households | 10,194 | 50,009 | 116,716,292 |
| Household Size | 3.01 | 2.77 | 2.58 |
| Male Population | 49.78% | 48.63% | 49.27% |
| Female Population | 50.22% | 51.37% | 50.96% |
| Married Population | 51.25% | 61.87% | 47.02% |
| Single Population | 48.75% | 38.13% | 52.98% |
| ESTIMATED TOTAL POPULATION BY AGE | | | |
| Age 0 to 4 | 6.53% | 5.76% | 6.56% |
| Age 5 to 9 | 6.29% | 8.06% | 6.61% |
| Age 10 to 14 | 5.86% | 9.16% | 6.71% |
| Age 15 to 17 | 3.56% | 5.69% | 4.21% |
| Age 18 to 20 | 2.22% | 2.53% | 2.95% |
| Age 21 to 24 | 6.14% | 4.84% | 7.01% |
| Age 25 to 34 | 14.82% | 10.36% | 13.33% |
| Age 35 to 44 | 14.31% | 15.32% | 13.33% |
| Age 45 to 49 | 14.58% | 18.24% | 14.61% |
| Age 50 to 54 | 14.58% | 18.24% | 14.61% |
| Age 55 to 59 | 10.47% | 11.38% | 11.84% |
| Age 60 to 64 | 10.47% | 11.38% | 11.84% |
| Age 65 to 74 | 5.16% | 4.77% | 7.05% |
| Age 75 to 84 | 5.43% | 2.55% | 4.24% |
| Age 85 and over | 4.62% | 1.35% | 1.78% |
| RACE | | | |
| White | 48.70% | 76.45% | 72.41% |
| Black | 8.99% | 4.66% | 12.61% |
| Asian | 24.32% | 14.92% | 4.75% |
| American Indian | 0.69% | 0.15% | 0.95% |
| Other | 17.30% | 3.82% | 9.28% |
| Hispanic | 1.43% | 1.96% | 16.35% |
| Non-Hispanic | 98.57% | 98.04% | 83.65% |
| FAMILY | | | |
| Married, w/children | 35.31% | 47.78% | 30.42% |
| Married, no children | 41.66% | 38.43% | 42.46% |
| Single, w/children | 10.07% | 8.01% | 14.39% |
| Single, no children | 12.96% | 5.79% | 12.73% |
| Divorced | 7.31% | 6.37% | 10.62% |
| Separated | 7.70% | 2.35% | 4.97% |
| Widowed | 5.71% | 3.46% | 6.14% |
| Now Married | 51.12% | 61.27% | 46.32% |
| Never Married | 28.17% | 26.55% | 31.95% |
