| | Chapin, SC | Mokena, IL | United States |
| Population | 1,544 | 19,897 | 329,725,481 |
| Female Population | 56.1% | 49.8% | 50.5% |
| Male Population | 43.9% | 50.2% | 49.5% |
| Median Age | 37.4 | 42.8 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,433 | 18,673 | 309,327,143 |
| Population - 2000 | 628 | 14,583 | 285,036,114 |
| Population - 1990 | 282 | 6,128 | 251,960,433 |
| Pop. 2000 to Now | 165.0% | 37.5% | 15.6% |
| Pop. 1990 to Now | 490.1% | 227.2% | 30.8% |
| space4 | | | |
| Population Density | 767.0 | 2,206.6 | 93.4 |
| Land Area | 2.0 | 9.0 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Chapin, SC | Mokena, IL | United States |
| Age 0 to 4 | 7.4% | 5.0% | 5.9% |
| Age 5 to 9 | 8.7% | 6.3% | 6.1% |
| Age 10 to 14 | 6.3% | 7.0% | 6.6% |
| Age 15 to 17 | 3.4% | 3.9% | 3.9% |
| Age 18 to 20 | 2.6% | 3.1% | 4.0% |
| Age 21 to 24 | 6.0% | 4.6% | 5.2% |
| Age 25 to 34 | 10.7% | 11.0% | 13.8% |
| Age 35 to 44 | 17.9% | 11.6% | 12.9% |
| Age 45 to 54 | 13.0% | 15.3% | 12.6% |
| Age 55 to 59 | 7.3% | 8.7% | 6.7% |
| Age 60 to 64 | 5.1% | 8.4% | 6.3% |
| Age 65 to 74 | 5.0% | 9.2% | 9.6% |
| Age 75 to 84 | 3.4% | 4.9% | 4.5% |
| Age 85 and over | 3.2% | 1.0% | 1.9% |
| space1 | | | |
| Race | | | |
| | Chapin, SC | Mokena, IL | United States |
| White | 81.0% | 91.8% | 59.4% |
| Black | 11.5% | 1.5% | 12.2% |
| Asian | 1.1% | 0.9% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.0% | 0.4% |
| Two or More Races | 2.5% | 1.3% | 3.2% |
| Hispanic | 3.8% | 4.5% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Chapin, SC | Mokena, IL | United States |
| Married Population | 46.7% | 62.1% | 49.8% |
| Currently Married | 44.7% | 61.8% | 48.0% |
| Married but Separated | 2.0% | 0.3% | 1.8% |
| Single Population | 53.3% | 37.9% | 50.2% |
| Never Married | 30.4% | 27.0% | 33.8% |
| Divorced | 16.5% | 6.1% | 10.8% |
| Widowed | 6.3% | 4.7% | 5.6% |
| space5 | | | |
| Household Size | 2.51 | 2.79 | 2.60 |
| Households | 615 | 7,133 | 124,010,992 |
| Family Households | 389 | 5,419 | 80,755,759 |
| Married couple, w/children | 32.1% | 35.8% | 30.5% |
| Married couple, no children | 32.1% | 53.7% | 42.9% |
| Non Family Households | 226 | 1,714 | 43,255,233 |
| Single householder, w/children | 24.9% | 4.9% | 15.8% |
| Single householder, no children | 10.8% | 5.6% | 10.8% |