| | Gilbert, SC | Napa, CA | United States |
| Population | 580 | 79,700 | 329,725,481 |
| Female Population | 46.2% | 50.3% | 50.5% |
| Male Population | 53.8% | 49.7% | 49.5% |
| Median Age | 43.1 | 39.9 | 38.4 |
| space3 | | | |
| Population - 2010 | 566 | 77,187 | 309,327,143 |
| Population - 2000 | 500 | 72,585 | 285,036,114 |
| Population - 1990 | 324 | 61,842 | 251,960,433 |
| Pop. 2000 to Now | 31.4% | 6.1% | 15.6% |
| Pop. 1990 to Now | 102.8% | 24.6% | 30.8% |
| space4 | | | |
| Population Density | 214.0 | 4,439.9 | 93.4 |
| Land Area | 2.7 | 18.0 | 3,531,905.4 |
| Water Area | 0.1 | 0.3 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Gilbert, SC | Napa, CA | United States |
| Age 0 to 4 | 4.8% | 5.4% | 5.9% |
| Age 5 to 9 | 5.3% | 5.4% | 6.1% |
| Age 10 to 14 | 9.0% | 6.8% | 6.6% |
| Age 15 to 17 | 5.9% | 4.0% | 3.9% |
| Age 18 to 20 | 3.1% | 3.4% | 4.0% |
| Age 21 to 24 | 5.3% | 4.7% | 5.2% |
| Age 25 to 34 | 9.5% | 13.6% | 13.8% |
| Age 35 to 44 | 11.2% | 13.5% | 12.9% |
| Age 45 to 54 | 15.2% | 13.2% | 12.6% |
| Age 55 to 59 | 11.9% | 6.5% | 6.7% |
| Age 60 to 64 | 6.6% | 6.1% | 6.3% |
| Age 65 to 74 | 9.5% | 10.4% | 9.6% |
| Age 75 to 84 | 2.2% | 5.0% | 4.5% |
| Age 85 and over | 0.5% | 2.1% | 1.9% |
| space1 | | | |
| Race | | | |
| | Gilbert, SC | Napa, CA | United States |
| White | 87.2% | 53.0% | 59.4% |
| Black | 4.0% | 0.6% | 12.2% |
| Asian | 0.0% | 2.9% | 5.6% |
| Native American | 0.5% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.1% | 0.2% |
| Other | 0.0% | 0.4% | 0.4% |
| Two or More Races | 2.6% | 3.2% | 3.2% |
| Hispanic | 5.7% | 39.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Gilbert, SC | Napa, CA | United States |
| Married Population | 55.9% | 51.2% | 49.8% |
| Currently Married | 52.9% | 49.8% | 48.0% |
| Married but Separated | 3.0% | 1.4% | 1.8% |
| Single Population | 44.1% | 48.8% | 50.2% |
| Never Married | 25.4% | 32.2% | 33.8% |
| Divorced | 8.1% | 11.1% | 10.8% |
| Widowed | 10.7% | 5.5% | 5.6% |
| space5 | | | |
| Household Size | 2.53 | 2.71 | 2.60 |
| Households | 229 | 29,099 | 124,010,992 |
| Family Households | 166 | 19,393 | 80,755,759 |
| Married couple, w/children | 27.7% | 32.1% | 30.5% |
| Married couple, no children | 45.2% | 44.4% | 42.9% |
| Non Family Households | 63 | 9,706 | 43,255,233 |
| Single householder, w/children | 23.5% | 13.6% | 15.8% |
| Single householder, no children | 3.6% | 9.9% | 10.8% |