| | Gwynn, VA | East Moriches, NY | United States |
| Population | 717 | 5,124 | 329,725,481 |
| Female Population | 51.1% | 45.9% | 50.5% |
| Male Population | 49.0% | 54.1% | 49.5% |
| Median Age | 53.2 | 47.7 | 38.4 |
| space3 | | | |
| Population - 2010 | 537 | 4,880 | 309,327,143 |
| Population - 2000 | 705 | 4,550 | 285,036,114 |
| Population - 1990 | 648 | 4,021 | 251,960,433 |
| Pop. 2000 to Now | -40.0% | 12.4% | 15.6% |
| Pop. 1990 to Now | -34.7% | 27.2% | 30.8% |
| space4 | | | |
| Population Density | 305.8 | 931.8 | 93.4 |
| Land Area | 2.3 | 5.5 | 3,531,905.4 |
| Water Area | 3.1 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Gwynn, VA | East Moriches, NY | United States |
| Age 0 to 4 | 0.0% | 3.7% | 5.9% |
| Age 5 to 9 | 0.0% | 5.9% | 6.1% |
| Age 10 to 14 | 0.0% | 8.0% | 6.6% |
| Age 15 to 17 | 0.0% | 3.5% | 3.9% |
| Age 18 to 20 | 0.0% | 3.9% | 4.0% |
| Age 21 to 24 | 20.2% | 3.4% | 5.2% |
| Age 25 to 34 | 3.1% | 6.7% | 13.8% |
| Age 35 to 44 | 9.2% | 11.5% | 12.9% |
| Age 45 to 54 | 21.5% | 14.5% | 12.6% |
| Age 55 to 59 | 0.0% | 7.3% | 6.7% |
| Age 60 to 64 | 16.6% | 9.0% | 6.3% |
| Age 65 to 74 | 16.6% | 14.0% | 9.6% |
| Age 75 to 84 | 12.8% | 6.0% | 4.5% |
| Age 85 and over | 0.0% | 2.3% | 1.9% |
| space1 | | | |
| Race | | | |
| | Gwynn, VA | East Moriches, NY | United States |
| White | 94.1% | 92.4% | 59.4% |
| Black | 0.0% | 0.9% | 12.2% |
| Asian | 0.0% | 2.0% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.7% | 0.4% |
| Two or More Races | 5.9% | 2.9% | 3.2% |
| Hispanic | 0.0% | 1.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Gwynn, VA | East Moriches, NY | United States |
| Married Population | 61.8% | 62.6% | 49.8% |
| Currently Married | 61.8% | 61.4% | 48.0% |
| Married but Separated | 0.0% | 1.2% | 1.8% |
| Single Population | 38.2% | 37.4% | 50.2% |
| Never Married | 25.0% | 24.5% | 33.8% |
| Divorced | 13.3% | 6.5% | 10.8% |
| Widowed | 0.0% | 6.4% | 5.6% |
| space5 | | | |
| Household Size | 2.06 | 2.66 | 2.60 |
| Households | 348 | 1,871 | 124,010,992 |
| Family Households | 192 | 1,437 | 80,755,759 |
| Married couple, w/children | 0.0% | 26.3% | 30.5% |
| Married couple, no children | 92.2% | 61.9% | 42.9% |
| Non Family Households | 156 | 434 | 43,255,233 |
| Single householder, w/children | 0.0% | 8.5% | 15.8% |
| Single householder, no children | 7.8% | 3.3% | 10.8% |