| | Greenville, GA | Crystal River, FL | United States |
| Population | 1,186 | 3,291 | 329,725,481 |
| Female Population | 53.2% | 53.5% | 50.5% |
| Male Population | 46.8% | 46.5% | 49.5% |
| Median Age | 41.9 | 61.2 | 38.4 |
| space3 | | | |
| Population - 2010 | 873 | 3,094 | 309,327,143 |
| Population - 2000 | 946 | 3,485 | 285,036,114 |
| Population - 1990 | 1,167 | 4,044 | 251,960,433 |
| Pop. 2000 to Now | -11.7% | -7.2% | 15.6% |
| Pop. 1990 to Now | -28.5% | -20.0% | 30.8% |
| space4 | | | |
| Population Density | 506.0 | 439.7 | 93.4 |
| Land Area | 2.3 | 7.5 | 3,531,905.4 |
| Water Area | 0.0 | 0.6 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Greenville, GA | Crystal River, FL | United States |
| Age 0 to 4 | 3.1% | 3.5% | 5.9% |
| Age 5 to 9 | 3.8% | 0.3% | 6.1% |
| Age 10 to 14 | 8.9% | 6.1% | 6.6% |
| Age 15 to 17 | 2.2% | 3.8% | 3.9% |
| Age 18 to 20 | 3.3% | 4.1% | 4.0% |
| Age 21 to 24 | 6.8% | 2.4% | 5.2% |
| Age 25 to 34 | 12.4% | 7.6% | 13.8% |
| Age 35 to 44 | 14.2% | 3.6% | 12.9% |
| Age 45 to 54 | 20.3% | 8.1% | 12.6% |
| Age 55 to 59 | 10.0% | 8.5% | 6.7% |
| Age 60 to 64 | 3.6% | 5.8% | 6.3% |
| Age 65 to 74 | 8.8% | 16.2% | 9.6% |
| Age 75 to 84 | 1.2% | 16.5% | 4.5% |
| Age 85 and over | 1.3% | 13.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Greenville, GA | Crystal River, FL | United States |
| White | 28.2% | 82.6% | 59.4% |
| Black | 67.8% | 10.7% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 0.0% | 0.6% | 0.6% |
| Hawaiian, Pacific Islander | 0.9% | 0.7% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 1.7% | 1.2% | 3.2% |
| Hispanic | 1.4% | 4.2% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Greenville, GA | Crystal River, FL | United States |
| Married Population | 47.8% | 51.6% | 49.8% |
| Currently Married | 40.1% | 51.6% | 48.0% |
| Married but Separated | 7.7% | 0.0% | 1.8% |
| Single Population | 52.2% | 48.4% | 50.2% |
| Never Married | 38.7% | 22.9% | 33.8% |
| Divorced | 7.0% | 12.7% | 10.8% |
| Widowed | 6.5% | 12.8% | 5.6% |
| space5 | | | |
| Household Size | 2.36 | 1.96 | 2.60 |
| Households | 503 | 1,561 | 124,010,992 |
| Family Households | 340 | 895 | 80,755,759 |
| Married couple, w/children | 21.5% | 9.7% | 30.5% |
| Married couple, no children | 36.8% | 72.3% | 42.9% |
| Non Family Households | 163 | 666 | 43,255,233 |
| Single householder, w/children | 27.6% | 11.4% | 15.8% |
| Single householder, no children | 14.1% | 6.6% | 10.8% |