| | Hornell, NY | Amherst, OH | United States |
| Population | 8,284 | 12,665 | 329,725,481 |
| Female Population | 49.4% | 49.9% | 50.5% |
| Male Population | 50.6% | 50.1% | 49.5% |
| Median Age | 41.3 | 42.9 | 38.4 |
| space3 | | | |
| Population - 2010 | 8,586 | 12,018 | 309,327,143 |
| Population - 2000 | 9,019 | 11,797 | 285,036,114 |
| Population - 1990 | 9,877 | 10,332 | 251,960,433 |
| Pop. 2000 to Now | -8.9% | 5.0% | 15.6% |
| Pop. 1990 to Now | -16.8% | 19.9% | 30.8% |
| space4 | | | |
| Population Density | 2,526.4 | 1,793.4 | 93.4 |
| Land Area | 3.3 | 7.1 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Hornell, NY | Amherst, OH | United States |
| Age 0 to 4 | 5.8% | 5.2% | 5.9% |
| Age 5 to 9 | 3.9% | 5.7% | 6.1% |
| Age 10 to 14 | 5.8% | 7.1% | 6.6% |
| Age 15 to 17 | 4.5% | 4.3% | 3.9% |
| Age 18 to 20 | 4.5% | 2.6% | 4.0% |
| Age 21 to 24 | 5.8% | 2.8% | 5.2% |
| Age 25 to 34 | 13.5% | 11.5% | 13.8% |
| Age 35 to 44 | 11.1% | 13.4% | 12.9% |
| Age 45 to 54 | 10.2% | 10.0% | 12.6% |
| Age 55 to 59 | 7.6% | 6.7% | 6.7% |
| Age 60 to 64 | 6.4% | 9.4% | 6.3% |
| Age 65 to 74 | 12.4% | 12.6% | 9.6% |
| Age 75 to 84 | 6.0% | 6.0% | 4.5% |
| Age 85 and over | 2.5% | 2.8% | 1.9% |
| space1 | | | |
| Race | | | |
| | Hornell, NY | Amherst, OH | United States |
| White | 90.8% | 87.2% | 59.4% |
| Black | 1.2% | 1.4% | 12.2% |
| Asian | 1.2% | 2.0% | 5.6% |
| Native American | 0.0% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 1.3% | 0.1% | 0.4% |
| Two or More Races | 2.5% | 3.0% | 3.2% |
| Hispanic | 3.0% | 6.3% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Hornell, NY | Amherst, OH | United States |
| Married Population | 39.0% | 55.4% | 49.8% |
| Currently Married | 36.4% | 55.0% | 48.0% |
| Married but Separated | 2.6% | 0.4% | 1.8% |
| Single Population | 61.0% | 44.6% | 50.2% |
| Never Married | 36.5% | 28.7% | 33.8% |
| Divorced | 18.5% | 8.6% | 10.8% |
| Widowed | 6.0% | 7.3% | 5.6% |
| space5 | | | |
| Household Size | 2.25 | 2.58 | 2.60 |
| Households | 3,599 | 4,866 | 124,010,992 |
| Family Households | 2,099 | 3,340 | 80,755,759 |
| Married couple, w/children | 17.8% | 28.4% | 30.5% |
| Married couple, no children | 37.0% | 51.6% | 42.9% |
| Non Family Households | 1,500 | 1,526 | 43,255,233 |
| Single householder, w/children | 30.0% | 11.6% | 15.8% |
| Single householder, no children | 15.3% | 8.4% | 10.8% |