| | Petersburg, PA | Carrollton, OH | United States |
| Population | 337 | 3,186 | 329,725,481 |
| Female Population | 49.3% | 52.1% | 50.5% |
| Male Population | 50.7% | 47.9% | 49.5% |
| Median Age | 41.8 | 45 | 38.4 |
| space3 | | | |
| Population - 2010 | 482 | 3,243 | 309,327,143 |
| Population - 2000 | 455 | 3,190 | 285,036,114 |
| Population - 1990 | 469 | 3,042 | 251,960,433 |
| Pop. 2000 to Now | 1.1% | -5.4% | 15.6% |
| Pop. 1990 to Now | -1.9% | -0.8% | 30.8% |
| space4 | | | |
| Population Density | 1,012.0 | 1,157.7 | 93.4 |
| Land Area | 0.3 | 2.8 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Petersburg, PA | Carrollton, OH | United States |
| Age 0 to 4 | 5.0% | 0.5% | 5.9% |
| Age 5 to 9 | 5.9% | 6.7% | 6.1% |
| Age 10 to 14 | 6.2% | 8.1% | 6.6% |
| Age 15 to 17 | 5.9% | 4.1% | 3.9% |
| Age 18 to 20 | 2.4% | 2.4% | 4.0% |
| Age 21 to 24 | 4.7% | 4.8% | 5.2% |
| Age 25 to 34 | 8.6% | 12.3% | 13.8% |
| Age 35 to 44 | 16.0% | 11.1% | 12.9% |
| Age 45 to 54 | 11.3% | 13.3% | 12.6% |
| Age 55 to 59 | 1.8% | 8.2% | 6.7% |
| Age 60 to 64 | 4.7% | 4.4% | 6.3% |
| Age 65 to 74 | 9.2% | 9.7% | 9.6% |
| Age 75 to 84 | 12.8% | 9.3% | 4.5% |
| Age 85 and over | 5.3% | 5.1% | 1.9% |
| space1 | | | |
| Race | | | |
| | Petersburg, PA | Carrollton, OH | United States |
| White | 99.7% | 97.2% | 59.4% |
| Black | 0.0% | 2.2% | 12.2% |
| Asian | 0.0% | 0.0% | 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 | 0.3% | 0.0% | 3.2% |
| Hispanic | 0.0% | 0.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Petersburg, PA | Carrollton, OH | United States |
| Married Population | 42.3% | 49.7% | 49.8% |
| Currently Married | 40.1% | 47.3% | 48.0% |
| Married but Separated | 2.2% | 2.4% | 1.8% |
| Single Population | 57.7% | 50.3% | 50.2% |
| Never Married | 28.0% | 29.5% | 33.8% |
| Divorced | 16.1% | 16.5% | 10.8% |
| Widowed | 13.6% | 4.3% | 5.6% |
| space5 | | | |
| Household Size | 2.48 | 2.04 | 2.60 |
| Households | 136 | 1,476 | 124,010,992 |
| Family Households | 85 | 929 | 80,755,759 |
| Married couple, w/children | 24.7% | 20.2% | 30.5% |
| Married couple, no children | 43.5% | 49.3% | 42.9% |
| Non Family Households | 51 | 547 | 43,255,233 |
| Single householder, w/children | 21.2% | 17.3% | 15.8% |
| Single householder, no children | 10.6% | 13.1% | 10.8% |