| | Brookside, DE | Elkton, MD | United States |
| Population | 14,202 | 15,724 | 329,725,481 |
| Female Population | 53.6% | 49.1% | 50.5% |
| Male Population | 46.4% | 50.9% | 49.5% |
| Median Age | 34.8 | 36 | 38.4 |
| space3 | | | |
| Population - 2010 | 14,365 | 15,474 | 309,327,143 |
| Population - 2000 | 14,806 | 11,893 | 285,036,114 |
| Population - 1990 | 15,307 | 9,073 | 251,960,433 |
| Pop. 2000 to Now | -7.2% | 31.7% | 15.6% |
| Pop. 1990 to Now | -10.2% | 72.7% | 30.8% |
| space4 | | | |
| Population Density | 3,598.2 | 1,769.3 | 93.4 |
| Land Area | 3.9 | 8.9 | 3,531,905.4 |
| Water Area | 0.0 | 0.3 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Brookside, DE | Elkton, MD | United States |
| Age 0 to 4 | 7.5% | 5.6% | 5.9% |
| Age 5 to 9 | 4.8% | 6.4% | 6.1% |
| Age 10 to 14 | 6.9% | 5.2% | 6.6% |
| Age 15 to 17 | 3.3% | 4.1% | 3.9% |
| Age 18 to 20 | 3.0% | 3.9% | 4.0% |
| Age 21 to 24 | 4.9% | 7.1% | 5.2% |
| Age 25 to 34 | 19.9% | 17.1% | 13.8% |
| Age 35 to 44 | 13.9% | 12.1% | 12.9% |
| Age 45 to 54 | 9.1% | 13.5% | 12.6% |
| Age 55 to 59 | 7.0% | 6.0% | 6.7% |
| Age 60 to 64 | 6.3% | 5.8% | 6.3% |
| Age 65 to 74 | 8.4% | 8.8% | 9.6% |
| Age 75 to 84 | 3.7% | 2.9% | 4.5% |
| Age 85 and over | 1.2% | 1.5% | 1.9% |
| space1 | | | |
| Race | | | |
| | Brookside, DE | Elkton, MD | United States |
| White | 57.2% | 67.2% | 59.4% |
| Black | 17.6% | 14.9% | 12.2% |
| Asian | 7.0% | 2.6% | 5.6% |
| Native American | 0.3% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.3% | 0.0% | 0.4% |
| Two or More Races | 2.7% | 7.5% | 3.2% |
| Hispanic | 15.0% | 7.8% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Brookside, DE | Elkton, MD | United States |
| Married Population | 45.0% | 43.8% | 49.8% |
| Currently Married | 43.4% | 42.0% | 48.0% |
| Married but Separated | 1.7% | 1.8% | 1.8% |
| Single Population | 55.0% | 56.2% | 50.2% |
| Never Married | 38.2% | 38.2% | 33.8% |
| Divorced | 13.4% | 11.6% | 10.8% |
| Widowed | 3.4% | 6.5% | 5.6% |
| space5 | | | |
| Household Size | 2.61 | 2.57 | 2.60 |
| Households | 5,410 | 5,849 | 124,010,992 |
| Family Households | 3,309 | 3,851 | 80,755,759 |
| Married couple, w/children | 27.3% | 22.4% | 30.5% |
| Married couple, no children | 39.3% | 36.1% | 42.9% |
| Non Family Households | 2,101 | 1,998 | 43,255,233 |
| Single householder, w/children | 23.9% | 24.0% | 15.8% |
| Single householder, no children | 9.5% | 17.5% | 10.8% |