| | Harlowton, MT | Oroville, WA | United States |
| Population | 1,096 | 1,694 | 329,725,481 |
| Female Population | 58.9% | 51.2% | 50.5% |
| Male Population | 41.1% | 48.8% | 49.5% |
| Median Age | 47.5 | 40.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 990 | 1,711 | 309,327,143 |
| Population - 2000 | 1,062 | 1,653 | 285,036,114 |
| Population - 1990 | 1,049 | 1,505 | 251,960,433 |
| Pop. 2000 to Now | -6.0% | 2.1% | 15.6% |
| Pop. 1990 to Now | -4.9% | 12.2% | 30.8% |
| space4 | | | |
| Population Density | 1,750.8 | 1,003.0 | 93.4 |
| Land Area | 0.6 | 1.7 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Harlowton, MT | Oroville, WA | United States |
| Age 0 to 4 | 2.6% | 9.4% | 5.9% |
| Age 5 to 9 | 7.9% | 8.0% | 6.1% |
| Age 10 to 14 | 7.2% | 6.2% | 6.6% |
| Age 15 to 17 | 1.6% | 3.9% | 3.9% |
| Age 18 to 20 | 1.1% | 2.7% | 4.0% |
| Age 21 to 24 | 2.6% | 3.6% | 5.2% |
| Age 25 to 34 | 12.7% | 12.1% | 13.8% |
| Age 35 to 44 | 9.9% | 6.8% | 12.9% |
| Age 45 to 54 | 15.1% | 15.8% | 12.6% |
| Age 55 to 59 | 3.8% | 6.3% | 6.7% |
| Age 60 to 64 | 4.5% | 7.3% | 6.3% |
| Age 65 to 74 | 18.2% | 11.0% | 9.6% |
| Age 75 to 84 | 9.3% | 6.2% | 4.5% |
| Age 85 and over | 3.5% | 0.6% | 1.9% |
| space1 | | | |
| Race | | | |
| | Harlowton, MT | Oroville, WA | United States |
| White | 94.7% | 48.2% | 59.4% |
| Black | 0.0% | 0.0% | 12.2% |
| Asian | 0.0% | 0.2% | 5.6% |
| Native American | 1.1% | 1.5% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.2% | 0.4% |
| Two or More Races | 0.5% | 9.7% | 3.2% |
| Hispanic | 3.7% | 40.1% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Harlowton, MT | Oroville, WA | United States |
| Married Population | 50.9% | 44.1% | 49.8% |
| Currently Married | 50.9% | 41.4% | 48.0% |
| Married but Separated | 0.0% | 2.7% | 1.8% |
| Single Population | 49.1% | 55.9% | 50.2% |
| Never Married | 22.4% | 28.6% | 33.8% |
| Divorced | 13.1% | 16.3% | 10.8% |
| Widowed | 13.6% | 11.0% | 5.6% |
| space5 | | | |
| Household Size | 2.72 | 2.43 | 2.60 |
| Households | 393 | 696 | 124,010,992 |
| Family Households | 283 | 367 | 80,755,759 |
| Married couple, w/children | 26.9% | 32.2% | 30.5% |
| Married couple, no children | 47.0% | 36.0% | 42.9% |
| Non Family Households | 110 | 329 | 43,255,233 |
| Single householder, w/children | 16.3% | 18.8% | 15.8% |
| Single householder, no children | 9.9% | 13.1% | 10.8% |