| | Sedgewickville, MO | Marble Hill, MO | United States |
| Population | 151 | 1,704 | 329,725,481 |
| Female Population | 46.4% | 60.7% | 50.5% |
| Male Population | 53.6% | 39.3% | 49.5% |
| Median Age | 40.3 | 32.4 | 38.4 |
| space3 | | | |
| Population - 2010 | 173 | 1,492 | 309,327,143 |
| Population - 2000 | 197 | 1,502 | 285,036,114 |
| Population - 1990 | 138 | 1,447 | 251,960,433 |
| Pop. 2000 to Now | -15.2% | -2.8% | 15.6% |
| Pop. 1990 to Now | 21.0% | 0.9% | 30.8% |
| space4 | | | |
| Population Density | 235.9 | 1,030.2 | 93.4 |
| Land Area | 0.6 | 1.7 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Sedgewickville, MO | Marble Hill, MO | United States |
| Age 0 to 4 | 10.6% | 13.6% | 5.9% |
| Age 5 to 9 | 10.6% | 11.0% | 6.1% |
| Age 10 to 14 | 4.6% | 5.8% | 6.6% |
| Age 15 to 17 | 0.0% | 6.2% | 3.9% |
| Age 18 to 20 | 0.0% | 4.2% | 4.0% |
| Age 21 to 24 | 3.3% | 1.7% | 5.2% |
| Age 25 to 34 | 13.9% | 9.6% | 13.8% |
| Age 35 to 44 | 9.9% | 14.0% | 12.9% |
| Age 45 to 54 | 6.0% | 5.9% | 12.6% |
| Age 55 to 59 | 17.2% | 6.5% | 6.7% |
| Age 60 to 64 | 15.2% | 8.2% | 6.3% |
| Age 65 to 74 | 0.0% | 7.8% | 9.6% |
| Age 75 to 84 | 8.6% | 3.9% | 4.5% |
| Age 85 and over | 0.0% | 1.6% | 1.9% |
| space1 | | | |
| Race | | | |
| | Sedgewickville, MO | Marble Hill, MO | United States |
| White | 100.0% | 89.6% | 59.4% |
| Black | 0.0% | 1.3% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 0.0% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 1.3% | 0.4% |
| Two or More Races | 0.0% | 5.0% | 3.2% |
| Hispanic | 0.0% | 2.7% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Sedgewickville, MO | Marble Hill, MO | United States |
| Married Population | 73.2% | 34.6% | 49.8% |
| Currently Married | 73.2% | 33.6% | 48.0% |
| Married but Separated | 0.0% | 0.9% | 1.8% |
| Single Population | 26.8% | 65.4% | 50.2% |
| Never Married | 10.7% | 26.2% | 33.8% |
| Divorced | 14.3% | 24.7% | 10.8% |
| Widowed | 1.8% | 14.5% | 5.6% |
| space5 | | | |
| Household Size | 2.65 | 2.83 | 2.60 |
| Households | 57 | 574 | 124,010,992 |
| Family Households | 46 | 303 | 80,755,759 |
| Married couple, w/children | 21.7% | 22.4% | 30.5% |
| Married couple, no children | 71.7% | 36.6% | 42.9% |
| Non Family Households | 11 | 271 | 43,255,233 |
| Single householder, w/children | 6.5% | 38.0% | 15.8% |
| Single householder, no children | 0.0% | 3.0% | 10.8% |