| | Peru, NE | Moorhead, MN | United States |
| Population | 833 | 44,129 | 329,725,481 |
| Female Population | 49.6% | 50.0% | 50.5% |
| Male Population | 50.4% | 50.0% | 49.5% |
| Median Age | 21.2 | 31 | 38.4 |
| space3 | | | |
| Population - 2010 | 769 | 39,568 | 309,327,143 |
| Population - 2000 | 569 | 32,177 | 285,036,114 |
| Population - 1990 | 1,110 | 32,295 | 251,960,433 |
| Pop. 2000 to Now | 39.2% | 36.8% | 15.6% |
| Pop. 1990 to Now | -28.7% | 36.3% | 30.8% |
| space4 | | | |
| Population Density | 1,583.7 | 1,975.4 | 93.4 |
| Land Area | 0.5 | 22.3 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Peru, NE | Moorhead, MN | United States |
| Age 0 to 4 | 2.3% | 7.0% | 5.9% |
| Age 5 to 9 | 3.7% | 6.7% | 6.1% |
| Age 10 to 14 | 3.8% | 6.0% | 6.6% |
| Age 15 to 17 | 1.2% | 3.6% | 3.9% |
| Age 18 to 20 | 37.2% | 10.4% | 4.0% |
| Age 21 to 24 | 14.5% | 7.8% | 5.2% |
| Age 25 to 34 | 7.7% | 14.9% | 13.8% |
| Age 35 to 44 | 6.5% | 12.4% | 12.9% |
| Age 45 to 54 | 5.2% | 9.6% | 12.6% |
| Age 55 to 59 | 6.1% | 5.7% | 6.7% |
| Age 60 to 64 | 3.0% | 4.0% | 6.3% |
| Age 65 to 74 | 7.3% | 6.8% | 9.6% |
| Age 75 to 84 | 1.4% | 3.0% | 4.5% |
| Age 85 and over | 0.0% | 2.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | Peru, NE | Moorhead, MN | United States |
| White | 79.5% | 83.4% | 59.4% |
| Black | 7.1% | 6.0% | 12.2% |
| Asian | 0.4% | 2.0% | 5.6% |
| Native American | 0.0% | 1.4% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.3% | 0.2% |
| Other | 0.0% | 0.1% | 0.4% |
| Two or More Races | 2.6% | 2.2% | 3.2% |
| Hispanic | 10.4% | 4.7% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Peru, NE | Moorhead, MN | United States |
| Married Population | 20.5% | 44.6% | 49.8% |
| Currently Married | 20.1% | 43.3% | 48.0% |
| Married but Separated | 0.4% | 1.3% | 1.8% |
| Single Population | 79.5% | 55.4% | 50.2% |
| Never Married | 71.4% | 41.8% | 33.8% |
| Divorced | 5.1% | 8.9% | 10.8% |
| Widowed | 3.1% | 4.7% | 5.6% |
| space5 | | | |
| Household Size | 2.06 | 2.38 | 2.60 |
| Households | 251 | 17,169 | 124,010,992 |
| Family Households | 102 | 9,540 | 80,755,759 |
| Married couple, w/children | 28.4% | 37.6% | 30.5% |
| Married couple, no children | 58.8% | 41.2% | 42.9% |
| Non Family Households | 149 | 7,629 | 43,255,233 |
| Single householder, w/children | 8.8% | 15.4% | 15.8% |
| Single householder, no children | 3.9% | 5.8% | 10.8% |