| | Lynbrook, NY | East Rockaway, NY | United States |
| Population | 20,325 | 10,108 | 329,725,481 |
| Female Population | 52.5% | 54.4% | 50.5% |
| Male Population | 47.5% | 45.6% | 49.5% |
| Median Age | 43.8 | 40.4 | 38.4 |
| space3 | | | |
| Population - 2010 | 19,481 | 9,776 | 309,327,143 |
| Population - 2000 | 19,911 | 10,414 | 285,036,114 |
| Population - 1990 | 19,208 | 10,152 | 251,960,433 |
| Pop. 2000 to Now | -3.1% | -6.1% | 15.6% |
| Pop. 1990 to Now | 0.4% | -3.7% | 30.8% |
| space4 | | | |
| Population Density | 10,096.9 | 9,948.8 | 93.4 |
| Land Area | 2.0 | 1.0 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Lynbrook, NY | East Rockaway, NY | United States |
| Age 0 to 4 | 6.4% | 5.0% | 5.9% |
| Age 5 to 9 | 4.3% | 8.5% | 6.1% |
| Age 10 to 14 | 5.3% | 6.3% | 6.6% |
| Age 15 to 17 | 3.2% | 2.9% | 3.9% |
| Age 18 to 20 | 2.6% | 2.0% | 4.0% |
| Age 21 to 24 | 4.7% | 4.9% | 5.2% |
| Age 25 to 34 | 13.5% | 13.1% | 13.8% |
| Age 35 to 44 | 12.0% | 12.8% | 12.9% |
| Age 45 to 54 | 12.3% | 11.3% | 12.6% |
| Age 55 to 59 | 7.2% | 7.7% | 6.7% |
| Age 60 to 64 | 8.3% | 8.8% | 6.3% |
| Age 65 to 74 | 10.0% | 11.0% | 9.6% |
| Age 75 to 84 | 6.3% | 3.7% | 4.5% |
| Age 85 and over | 3.9% | 1.8% | 1.9% |
| space1 | | | |
| Race | | | |
| | Lynbrook, NY | East Rockaway, NY | United States |
| White | 64.4% | 73.3% | 59.4% |
| Black | 3.7% | 8.7% | 12.2% |
| Asian | 7.7% | 4.0% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.3% | 0.3% | 0.4% |
| Two or More Races | 1.5% | 1.7% | 3.2% |
| Hispanic | 22.5% | 12.1% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Lynbrook, NY | East Rockaway, NY | United States |
| Married Population | 55.7% | 52.5% | 49.8% |
| Currently Married | 54.1% | 50.9% | 48.0% |
| Married but Separated | 1.6% | 1.7% | 1.8% |
| Single Population | 44.3% | 47.5% | 50.2% |
| Never Married | 29.9% | 32.8% | 33.8% |
| Divorced | 7.2% | 6.4% | 10.8% |
| Widowed | 7.2% | 8.3% | 5.6% |
| space5 | | | |
| Household Size | 2.85 | 2.61 | 2.60 |
| Households | 7,119 | 3,804 | 124,010,992 |
| Family Households | 5,153 | 2,640 | 80,755,759 |
| Married couple, w/children | 32.6% | 30.5% | 30.5% |
| Married couple, no children | 44.6% | 41.6% | 42.9% |
| Non Family Households | 1,966 | 1,164 | 43,255,233 |
| Single householder, w/children | 9.7% | 15.9% | 15.8% |
| Single householder, no children | 13.1% | 12.0% | 10.8% |