| | Bethany Beach, DE | Emerald Lake Hills, CA | United States |
| Population | 936 | 4,545 | 329,725,481 |
| Female Population | 55.7% | 48.8% | 50.5% |
| Male Population | 44.3% | 51.2% | 49.5% |
| Median Age | 66.9 | 47.6 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,058 | 4,445 | 309,327,143 |
| Population - 2000 | 903 | 3,899 | 285,036,114 |
| Population - 1990 | 326 | 3,328 | 251,960,433 |
| Pop. 2000 to Now | 42.1% | 18.1% | 15.6% |
| Pop. 1990 to Now | 293.6% | 38.3% | 30.8% |
| space4 | | | |
| Population Density | 813.2 | 3,803.4 | 93.4 |
| Land Area | 1.2 | 1.2 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Bethany Beach, DE | Emerald Lake Hills, CA | United States |
| Age 0 to 4 | 1.8% | 5.6% | 5.9% |
| Age 5 to 9 | 0.0% | 5.3% | 6.1% |
| Age 10 to 14 | 1.2% | 6.4% | 6.6% |
| Age 15 to 17 | 1.0% | 3.9% | 3.9% |
| Age 18 to 20 | 2.1% | 1.8% | 4.0% |
| Age 21 to 24 | 4.8% | 4.1% | 5.2% |
| Age 25 to 34 | 5.1% | 8.5% | 13.8% |
| Age 35 to 44 | 0.9% | 11.1% | 12.9% |
| Age 45 to 54 | 5.2% | 15.2% | 12.6% |
| Age 55 to 59 | 7.2% | 9.4% | 6.7% |
| Age 60 to 64 | 14.3% | 9.3% | 6.3% |
| Age 65 to 74 | 35.0% | 14.7% | 9.6% |
| Age 75 to 84 | 14.4% | 3.4% | 4.5% |
| Age 85 and over | 6.9% | 1.3% | 1.9% |
| space1 | | | |
| Race | | | |
| | Bethany Beach, DE | Emerald Lake Hills, CA | United States |
| White | 93.3% | 78.2% | 59.4% |
| Black | 0.0% | 0.5% | 12.2% |
| Asian | 4.5% | 7.3% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.6% | 5.3% | 3.2% |
| Hispanic | 1.6% | 8.8% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Bethany Beach, DE | Emerald Lake Hills, CA | United States |
| Married Population | 66.1% | 70.9% | 49.8% |
| Currently Married | 65.4% | 70.9% | 48.0% |
| Married but Separated | 0.7% | 0.0% | 1.8% |
| Single Population | 33.9% | 29.1% | 50.2% |
| Never Married | 19.8% | 22.2% | 33.8% |
| Divorced | 5.5% | 3.5% | 10.8% |
| Widowed | 8.6% | 3.4% | 5.6% |
| space5 | | | |
| Household Size | 2.03 | 2.86 | 2.60 |
| Households | 461 | 1,572 | 124,010,992 |
| Family Households | 305 | 1,376 | 80,755,759 |
| Married couple, w/children | 8.2% | 37.2% | 30.5% |
| Married couple, no children | 84.6% | 56.2% | 42.9% |
| Non Family Households | 156 | 196 | 43,255,233 |
| Single householder, w/children | 1.6% | 2.2% | 15.8% |
| Single householder, no children | 5.6% | 4.4% | 10.8% |