| | Delphos, OH | Bucyrus, OH | United States |
| Population | 7,165 | 11,690 | 329,725,481 |
| Female Population | 50.9% | 48.0% | 50.5% |
| Male Population | 49.1% | 52.0% | 49.5% |
| Median Age | 38 | 42.7 | 38.4 |
| space3 | | | |
| Population - 2010 | 7,117 | 12,379 | 309,327,143 |
| Population - 2000 | 6,944 | 13,224 | 285,036,114 |
| Population - 1990 | 7,093 | 13,496 | 251,960,433 |
| Pop. 2000 to Now | -0.7% | -11.2% | 15.6% |
| Pop. 1990 to Now | -2.8% | -13.0% | 30.8% |
| space4 | | | |
| Population Density | 2,054.2 | 1,583.2 | 93.4 |
| Land Area | 3.5 | 7.4 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Delphos, OH | Bucyrus, OH | United States |
| Age 0 to 4 | 9.3% | 6.4% | 5.9% |
| Age 5 to 9 | 5.5% | 6.7% | 6.1% |
| Age 10 to 14 | 4.6% | 6.4% | 6.6% |
| Age 15 to 17 | 3.0% | 2.8% | 3.9% |
| Age 18 to 20 | 2.1% | 2.7% | 4.0% |
| Age 21 to 24 | 5.5% | 3.9% | 5.2% |
| Age 25 to 34 | 17.2% | 13.4% | 13.8% |
| Age 35 to 44 | 9.5% | 10.8% | 12.9% |
| Age 45 to 54 | 9.9% | 11.3% | 12.6% |
| Age 55 to 59 | 5.7% | 6.9% | 6.7% |
| Age 60 to 64 | 7.4% | 6.6% | 6.3% |
| Age 65 to 74 | 9.0% | 11.4% | 9.6% |
| Age 75 to 84 | 8.0% | 6.2% | 4.5% |
| Age 85 and over | 3.2% | 4.4% | 1.9% |
| space1 | | | |
| Race | | | |
| | Delphos, OH | Bucyrus, OH | United States |
| White | 93.5% | 93.2% | 59.4% |
| Black | 1.5% | 0.9% | 12.2% |
| Asian | 0.0% | 1.8% | 5.6% |
| Native American | 0.0% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 1.4% | 2.1% | 3.2% |
| Hispanic | 3.6% | 2.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Delphos, OH | Bucyrus, OH | United States |
| Married Population | 53.1% | 50.0% | 49.8% |
| Currently Married | 51.7% | 47.8% | 48.0% |
| Married but Separated | 1.4% | 2.2% | 1.8% |
| Single Population | 46.9% | 50.0% | 50.2% |
| Never Married | 24.7% | 24.7% | 33.8% |
| Divorced | 13.1% | 16.3% | 10.8% |
| Widowed | 9.2% | 9.0% | 5.6% |
| space5 | | | |
| Household Size | 2.26 | 2.18 | 2.60 |
| Households | 3,110 | 5,225 | 124,010,992 |
| Family Households | 1,948 | 2,976 | 80,755,759 |
| Married couple, w/children | 27.4% | 24.8% | 30.5% |
| Married couple, no children | 43.2% | 46.2% | 42.9% |
| Non Family Households | 1,162 | 2,249 | 43,255,233 |
| Single householder, w/children | 21.7% | 21.3% | 15.8% |
| Single householder, no children | 7.8% | 7.7% | 10.8% |