| | Cookeville, TN | Niagara Falls, NY | United States |
| Population | 34,068 | 48,763 | 329,725,481 |
| Female Population | 51.1% | 51.6% | 50.5% |
| Male Population | 48.9% | 48.4% | 49.5% |
| Median Age | 30 | 40.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 31,206 | 49,996 | 309,327,143 |
| Population - 2000 | 23,923 | 55,593 | 285,036,114 |
| Population - 1990 | 21,744 | 61,840 | 251,960,433 |
| Pop. 2000 to Now | 46.6% | -14.8% | 15.6% |
| Pop. 1990 to Now | 61.2% | -23.4% | 30.8% |
| space4 | | | |
| Population Density | 962.8 | 3,461.8 | 93.4 |
| Land Area | 35.4 | 14.1 | 3,531,905.4 |
| Water Area | 0.2 | 2.7 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Cookeville, TN | Niagara Falls, NY | United States |
| Age 0 to 4 | 5.8% | 6.5% | 5.9% |
| Age 5 to 9 | 5.0% | 6.0% | 6.1% |
| Age 10 to 14 | 6.0% | 6.0% | 6.6% |
| Age 15 to 17 | 3.2% | 3.3% | 3.9% |
| Age 18 to 20 | 10.5% | 3.1% | 4.0% |
| Age 21 to 24 | 11.9% | 4.9% | 5.2% |
| Age 25 to 34 | 13.6% | 12.9% | 13.8% |
| Age 35 to 44 | 11.1% | 12.2% | 12.9% |
| Age 45 to 54 | 10.7% | 12.2% | 12.6% |
| Age 55 to 59 | 3.5% | 7.5% | 6.7% |
| Age 60 to 64 | 5.0% | 8.0% | 6.3% |
| Age 65 to 74 | 7.7% | 10.4% | 9.6% |
| Age 75 to 84 | 4.6% | 4.2% | 4.5% |
| Age 85 and over | 1.5% | 2.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Cookeville, TN | Niagara Falls, NY | United States |
| White | 81.3% | 65.3% | 59.4% |
| Black | 4.1% | 19.7% | 12.2% |
| Asian | 1.8% | 1.7% | 5.6% |
| Native American | 0.1% | 0.8% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.4% | 0.4% |
| Two or More Races | 3.4% | 5.5% | 3.2% |
| Hispanic | 9.2% | 6.5% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Cookeville, TN | Niagara Falls, NY | United States |
| Married Population | 40.0% | 38.4% | 49.8% |
| Currently Married | 37.5% | 35.9% | 48.0% |
| Married but Separated | 2.5% | 2.5% | 1.8% |
| Single Population | 60.0% | 61.6% | 50.2% |
| Never Married | 42.8% | 41.4% | 33.8% |
| Divorced | 11.6% | 13.0% | 10.8% |
| Widowed | 5.6% | 7.3% | 5.6% |
| space5 | | | |
| Household Size | 2.23 | 2.19 | 2.60 |
| Households | 13,982 | 22,130 | 124,010,992 |
| Family Households | 7,405 | 11,657 | 80,755,759 |
| Married couple, w/children | 27.2% | 18.1% | 30.5% |
| Married couple, no children | 40.5% | 38.4% | 42.9% |
| Non Family Households | 6,577 | 10,473 | 43,255,233 |
| Single householder, w/children | 20.4% | 29.0% | 15.8% |
| Single householder, no children | 12.0% | 14.5% | 10.8% |