| | Elwood, IN | McKinleyville, CA | United States |
| Population | 8,295 | 16,457 | 329,725,481 |
| Female Population | 54.2% | 50.3% | 50.5% |
| Male Population | 45.8% | 49.8% | 49.5% |
| Median Age | 40.6 | 37.4 | 38.4 |
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| Population - 2010 | 8,603 | 16,896 | 309,327,143 |
| Population - 2000 | 9,737 | 13,599 | 285,036,114 |
| Population - 1990 | 9,494 | 10,749 | 251,960,433 |
| Pop. 2000 to Now | -14.0% | 24.6% | 15.6% |
| Pop. 1990 to Now | -11.7% | 57.6% | 30.8% |
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| Population Density | 2,231.0 | 790.0 | 93.4 |
| Land Area | 3.7 | 20.8 | 3,531,905.4 |
| Water Area | 0.0 | 0.2 | 264,836.8 |
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| Est. Total Population By Age | | | |
| | Elwood, IN | McKinleyville, CA | United States |
| Age 0 to 4 | 7.3% | 7.6% | 5.9% |
| Age 5 to 9 | 4.3% | 7.2% | 6.1% |
| Age 10 to 14 | 6.6% | 4.0% | 6.6% |
| Age 15 to 17 | 4.1% | 3.1% | 3.9% |
| Age 18 to 20 | 3.1% | 5.5% | 4.0% |
| Age 21 to 24 | 8.1% | 6.0% | 5.2% |
| Age 25 to 34 | 10.5% | 14.3% | 13.8% |
| Age 35 to 44 | 14.3% | 13.6% | 12.9% |
| Age 45 to 54 | 13.1% | 10.5% | 12.6% |
| Age 55 to 59 | 6.8% | 5.0% | 6.7% |
| Age 60 to 64 | 6.5% | 7.8% | 6.3% |
| Age 65 to 74 | 8.0% | 9.7% | 9.6% |
| Age 75 to 84 | 5.7% | 4.4% | 4.5% |
| Age 85 and over | 1.6% | 1.3% | 1.9% |
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| Race | | | |
| | Elwood, IN | McKinleyville, CA | United States |
| White | 93.4% | 71.2% | 59.4% |
| Black | 0.6% | 0.4% | 12.2% |
| Asian | 0.1% | 4.4% | 5.6% |
| Native American | 0.0% | 4.2% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.0% | 0.4% |
| Two or More Races | 1.2% | 9.5% | 3.2% |
| Hispanic | 4.6% | 10.3% | 18.4% |
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| Marriage & Family | | | |
| | Elwood, IN | McKinleyville, CA | United States |
| Married Population | 41.2% | 45.5% | 49.8% |
| Currently Married | 39.6% | 44.3% | 48.0% |
| Married but Separated | 1.6% | 1.3% | 1.8% |
| Single Population | 58.8% | 54.5% | 50.2% |
| Never Married | 29.1% | 37.1% | 33.8% |
| Divorced | 22.4% | 11.9% | 10.8% |
| Widowed | 7.3% | 5.4% | 5.6% |
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| Household Size | 2.53 | 2.55 | 2.60 |
| Households | 3,276 | 6,442 | 124,010,992 |
| Family Households | 2,138 | 3,469 | 80,755,759 |
| Married couple, w/children | 20.6% | 34.2% | 30.5% |
| Married couple, no children | 40.8% | 43.2% | 42.9% |
| Non Family Households | 1,138 | 2,973 | 43,255,233 |
| Single householder, w/children | 20.1% | 14.5% | 15.8% |
| Single householder, no children | 18.4% | 8.0% | 10.8% |