| | Riverdale, IA | Chamblee, GA | United States |
| Population | 394 | 29,894 | 329,725,481 |
| Female Population | 50.8% | 46.6% | 50.5% |
| Male Population | 49.2% | 53.4% | 49.5% |
| Median Age | 46 | 33.7 | 38.4 |
| space3 | | | |
| Population - 2010 | 387 | 27,016 | 309,327,143 |
| Population - 2000 | 656 | 9,552 | 285,036,114 |
| Population - 1990 | 433 | 7,668 | 251,960,433 |
| Pop. 2000 to Now | -39.3% | 222.9% | 15.6% |
| Pop. 1990 to Now | -8.1% | 302.2% | 30.8% |
| space4 | | | |
| Population Density | 214.7 | 3,880.3 | 93.4 |
| Land Area | 1.8 | 7.7 | 3,531,905.4 |
| Water Area | 0.4 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Riverdale, IA | Chamblee, GA | United States |
| Age 0 to 4 | 7.1% | 6.7% | 5.9% |
| Age 5 to 9 | 2.3% | 5.5% | 6.1% |
| Age 10 to 14 | 3.8% | 5.4% | 6.6% |
| Age 15 to 17 | 4.8% | 3.9% | 3.9% |
| Age 18 to 20 | 1.5% | 2.8% | 4.0% |
| Age 21 to 24 | 3.3% | 5.5% | 5.2% |
| Age 25 to 34 | 9.6% | 23.1% | 13.8% |
| Age 35 to 44 | 16.2% | 16.7% | 12.9% |
| Age 45 to 54 | 11.9% | 13.9% | 12.6% |
| Age 55 to 59 | 7.1% | 4.3% | 6.7% |
| Age 60 to 64 | 7.1% | 3.8% | 6.3% |
| Age 65 to 74 | 10.4% | 4.8% | 9.6% |
| Age 75 to 84 | 8.9% | 2.9% | 4.5% |
| Age 85 and over | 5.8% | 0.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Riverdale, IA | Chamblee, GA | United States |
| White | 77.7% | 35.7% | 59.4% |
| Black | 5.3% | 17.0% | 12.2% |
| Asian | 1.5% | 8.8% | 5.6% |
| Native American | 0.0% | 0.2% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 6.9% | 2.7% | 3.2% |
| Hispanic | 8.6% | 35.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Riverdale, IA | Chamblee, GA | United States |
| Married Population | 59.9% | 39.9% | 49.8% |
| Currently Married | 59.9% | 38.8% | 48.0% |
| Married but Separated | 0.0% | 1.1% | 1.8% |
| Single Population | 40.1% | 60.1% | 50.2% |
| Never Married | 23.7% | 48.2% | 33.8% |
| Divorced | 9.9% | 9.4% | 10.8% |
| Widowed | 6.4% | 2.5% | 5.6% |
| space5 | | | |
| Household Size | 2.30 | 2.40 | 2.60 |
| Households | 171 | 12,384 | 124,010,992 |
| Family Households | 108 | 5,878 | 80,755,759 |
| Married couple, w/children | 20.4% | 30.0% | 30.5% |
| Married couple, no children | 58.3% | 42.9% | 42.9% |
| Non Family Households | 63 | 6,506 | 43,255,233 |
| Single householder, w/children | 13.0% | 15.8% | 15.8% |
| Single householder, no children | 8.3% | 11.3% | 10.8% |