| | Northfield, KY | Spokane Valley, WA | United States |
| Population | 1,181 | 102,178 | 329,725,481 |
| Female Population | 48.6% | 50.2% | 50.5% |
| Male Population | 51.4% | 49.8% | 49.5% |
| Median Age | 50.1 | 38 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,021 | 90,052 | 309,327,143 |
| Population - 2000 | 970 | 79,368 | 285,036,114 |
| Population - 1990 | 898 | 70,020 | 251,960,433 |
| Pop. 2000 to Now | 8.5% | 29.6% | 15.6% |
| Pop. 1990 to Now | 17.2% | 47.0% | 30.8% |
| space4 | | | |
| Population Density | 2,507.4 | 2,708.5 | 93.4 |
| Land Area | 0.5 | 37.7 | 3,531,905.4 |
| Water Area | 0.0 | 0.3 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Northfield, KY | Spokane Valley, WA | United States |
| Age 0 to 4 | 7.3% | 6.6% | 5.9% |
| Age 5 to 9 | 5.1% | 6.4% | 6.1% |
| Age 10 to 14 | 6.8% | 5.7% | 6.6% |
| Age 15 to 17 | 2.6% | 3.3% | 3.9% |
| Age 18 to 20 | 0.8% | 2.7% | 4.0% |
| Age 21 to 24 | 3.2% | 5.0% | 5.2% |
| Age 25 to 34 | 7.5% | 16.4% | 13.8% |
| Age 35 to 44 | 9.9% | 12.6% | 12.9% |
| Age 45 to 54 | 18.5% | 12.0% | 12.6% |
| Age 55 to 59 | 6.9% | 5.9% | 6.7% |
| Age 60 to 64 | 10.1% | 6.3% | 6.3% |
| Age 65 to 74 | 6.9% | 9.8% | 9.6% |
| Age 75 to 84 | 8.2% | 5.0% | 4.5% |
| Age 85 and over | 6.3% | 2.3% | 1.9% |
| space1 | | | |
| Race | | | |
| | Northfield, KY | Spokane Valley, WA | United States |
| White | 89.1% | 83.7% | 59.4% |
| Black | 3.3% | 1.3% | 12.2% |
| Asian | 3.6% | 1.4% | 5.6% |
| Native American | 0.0% | 1.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.4% | 0.2% |
| Other | 0.0% | 0.2% | 0.4% |
| Two or More Races | 2.0% | 4.9% | 3.2% |
| Hispanic | 2.0% | 7.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Northfield, KY | Spokane Valley, WA | United States |
| Married Population | 65.7% | 47.7% | 49.8% |
| Currently Married | 63.7% | 46.6% | 48.0% |
| Married but Separated | 2.0% | 1.1% | 1.8% |
| Single Population | 34.3% | 52.3% | 50.2% |
| Never Married | 19.5% | 30.3% | 33.8% |
| Divorced | 6.6% | 15.1% | 10.8% |
| Widowed | 8.3% | 6.9% | 5.6% |
| space5 | | | |
| Household Size | 2.33 | 2.44 | 2.60 |
| Households | 478 | 41,569 | 124,010,992 |
| Family Households | 315 | 25,424 | 80,755,759 |
| Married couple, w/children | 30.8% | 29.4% | 30.5% |
| Married couple, no children | 60.6% | 42.8% | 42.9% |
| Non Family Households | 163 | 16,145 | 43,255,233 |
| Single householder, w/children | 4.8% | 17.3% | 15.8% |
| Single householder, no children | 3.8% | 10.5% | 10.8% |