| | Hillsboro, IA | Donnellson, IA | United States |
| Population | 148 | 960 | 329,725,481 |
| Female Population | 52.0% | 55.4% | 50.5% |
| Male Population | 48.0% | 44.6% | 49.5% |
| Median Age | 44.7 | 31.7 | 38.4 |
| space3 | | | |
| Population - 2010 | 178 | 906 | 309,327,143 |
| Population - 2000 | 205 | 963 | 285,036,114 |
| Population - 1990 | 151 | 940 | 251,960,433 |
| Pop. 2000 to Now | -15.6% | -12.2% | 15.6% |
| Pop. 1990 to Now | 14.6% | -10.0% | 30.8% |
| space4 | | | |
| Population Density | 294.2 | 920.4 | 93.4 |
| Land Area | 0.5 | 1.0 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Hillsboro, IA | Donnellson, IA | United States |
| Age 0 to 4 | 6.1% | 12.1% | 5.9% |
| Age 5 to 9 | 0.7% | 8.9% | 6.1% |
| Age 10 to 14 | 4.7% | 8.1% | 6.6% |
| Age 15 to 17 | 4.1% | 2.6% | 3.9% |
| Age 18 to 20 | 7.4% | 4.5% | 4.0% |
| Age 21 to 24 | 0.0% | 1.4% | 5.2% |
| Age 25 to 34 | 6.8% | 18.6% | 13.8% |
| Age 35 to 44 | 23.0% | 11.6% | 12.9% |
| Age 45 to 54 | 6.8% | 7.6% | 12.6% |
| Age 55 to 59 | 10.1% | 2.5% | 6.7% |
| Age 60 to 64 | 3.4% | 4.9% | 6.3% |
| Age 65 to 74 | 12.8% | 8.6% | 9.6% |
| Age 75 to 84 | 8.1% | 4.8% | 4.5% |
| Age 85 and over | 6.1% | 3.9% | 1.9% |
| space1 | | | |
| Race | | | |
| | Hillsboro, IA | Donnellson, IA | United States |
| White | 98.0% | 95.3% | 59.4% |
| Black | 0.0% | 2.9% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.0% | 1.6% | 3.2% |
| Hispanic | 2.0% | 0.2% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Hillsboro, IA | Donnellson, IA | United States |
| Married Population | 39.7% | 45.7% | 49.8% |
| Currently Married | 38.9% | 44.3% | 48.0% |
| Married but Separated | 0.8% | 1.3% | 1.8% |
| Single Population | 60.3% | 54.3% | 50.2% |
| Never Married | 38.2% | 31.0% | 33.8% |
| Divorced | 4.6% | 11.7% | 10.8% |
| Widowed | 17.6% | 11.6% | 5.6% |
| space5 | | | |
| Household Size | 2.35 | 2.51 | 2.60 |
| Households | 63 | 367 | 124,010,992 |
| Family Households | 37 | 240 | 80,755,759 |
| Married couple, w/children | 29.7% | 34.6% | 30.5% |
| Married couple, no children | 37.8% | 21.7% | 42.9% |
| Non Family Households | 26 | 127 | 43,255,233 |
| Single householder, w/children | 21.6% | 32.1% | 15.8% |
| Single householder, no children | 10.8% | 11.7% | 10.8% |