| | Radcliffe, IA | DeKalb, IL | United States |
| Population | 584 | 41,083 | 329,725,481 |
| Female Population | 56.2% | 50.4% | 50.5% |
| Male Population | 43.8% | 49.6% | 49.5% |
| Median Age | 49.6 | 25.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 546 | 44,107 | 309,327,143 |
| Population - 2000 | 607 | 39,018 | 285,036,114 |
| Population - 1990 | 574 | 34,925 | 251,960,433 |
| Pop. 2000 to Now | -14.8% | 9.2% | 15.6% |
| Pop. 1990 to Now | -9.9% | 22.0% | 30.8% |
| space4 | | | |
| Population Density | 585.8 | 2,545.6 | 93.4 |
| Land Area | 1.0 | 16.1 | 3,531,905.4 |
| Water Area | 0.0 | 0.2 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Radcliffe, IA | DeKalb, IL | United States |
| Age 0 to 4 | 3.6% | 5.1% | 5.9% |
| Age 5 to 9 | 7.4% | 5.2% | 6.1% |
| Age 10 to 14 | 5.8% | 5.6% | 6.6% |
| Age 15 to 17 | 4.3% | 3.1% | 3.9% |
| Age 18 to 20 | 0.0% | 13.0% | 4.0% |
| Age 21 to 24 | 3.1% | 17.9% | 5.2% |
| Age 25 to 34 | 8.2% | 14.5% | 13.8% |
| Age 35 to 44 | 9.8% | 9.4% | 12.9% |
| Age 45 to 54 | 13.4% | 8.2% | 12.6% |
| Age 55 to 59 | 8.0% | 4.9% | 6.7% |
| Age 60 to 64 | 16.4% | 3.5% | 6.3% |
| Age 65 to 74 | 10.1% | 5.5% | 9.6% |
| Age 75 to 84 | 5.8% | 2.4% | 4.5% |
| Age 85 and over | 4.1% | 1.8% | 1.9% |
| space1 | | | |
| Race | | | |
| | Radcliffe, IA | DeKalb, IL | United States |
| White | 93.5% | 60.5% | 59.4% |
| Black | 0.0% | 14.5% | 12.2% |
| Asian | 0.0% | 4.0% | 5.6% |
| Native American | 0.0% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.2% | 0.4% |
| Two or More Races | 1.5% | 4.6% | 3.2% |
| Hispanic | 5.0% | 16.1% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Radcliffe, IA | DeKalb, IL | United States |
| Married Population | 57.0% | 30.8% | 49.8% |
| Currently Married | 56.0% | 30.1% | 48.0% |
| Married but Separated | 1.0% | 0.8% | 1.8% |
| Single Population | 43.0% | 69.2% | 50.2% |
| Never Married | 16.3% | 58.0% | 33.8% |
| Divorced | 18.7% | 7.2% | 10.8% |
| Widowed | 8.0% | 4.0% | 5.6% |
| space5 | | | |
| Household Size | 2.43 | 2.35 | 2.60 |
| Households | 240 | 15,867 | 124,010,992 |
| Family Households | 154 | 7,826 | 80,755,759 |
| Married couple, w/children | 28.6% | 26.7% | 30.5% |
| Married couple, no children | 56.5% | 35.8% | 42.9% |
| Non Family Households | 86 | 8,041 | 43,255,233 |
| Single householder, w/children | 8.4% | 25.3% | 15.8% |
| Single householder, no children | 6.5% | 12.3% | 10.8% |