| | Plainville, CT | Vernal, UT | United States |
| Population | 17,514 | 10,037 | 329,725,481 |
| Female Population | 47.2% | 44.9% | 50.5% |
| Male Population | 52.8% | 55.2% | 49.5% |
| Median Age | 43.6 | 30.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 17,684 | 9,086 | 309,327,143 |
| Population - 2000 | 17,328 | 7,714 | 285,036,114 |
| Population - 1990 | 17,392 | 6,644 | 251,960,433 |
| Pop. 2000 to Now | 0.9% | 35.7% | 15.6% |
| Pop. 1990 to Now | 0.5% | 57.6% | 30.8% |
| space4 | | | |
| Population Density | 1,803.5 | 2,171.6 | 93.4 |
| Land Area | 9.7 | 4.6 | 3,531,905.4 |
| Water Area | 0.1 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Plainville, CT | Vernal, UT | United States |
| Age 0 to 4 | 3.4% | 11.1% | 5.9% |
| Age 5 to 9 | 4.1% | 8.5% | 6.1% |
| Age 10 to 14 | 5.5% | 7.0% | 6.6% |
| Age 15 to 17 | 3.5% | 4.1% | 3.9% |
| Age 18 to 20 | 3.5% | 3.5% | 4.0% |
| Age 21 to 24 | 5.3% | 7.6% | 5.2% |
| Age 25 to 34 | 13.2% | 15.8% | 13.8% |
| Age 35 to 44 | 13.6% | 12.6% | 12.9% |
| Age 45 to 54 | 13.5% | 11.2% | 12.6% |
| Age 55 to 59 | 6.7% | 6.8% | 6.7% |
| Age 60 to 64 | 8.2% | 3.3% | 6.3% |
| Age 65 to 74 | 10.8% | 4.5% | 9.6% |
| Age 75 to 84 | 5.5% | 1.8% | 4.5% |
| Age 85 and over | 3.5% | 2.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | Plainville, CT | Vernal, UT | United States |
| White | 80.1% | 82.7% | 59.4% |
| Black | 2.5% | 0.5% | 12.2% |
| Asian | 4.7% | 0.2% | 5.6% |
| Native American | 0.2% | 3.3% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.1% | 0.2% |
| Other | 0.1% | 0.0% | 0.4% |
| Two or More Races | 1.1% | 4.4% | 3.2% |
| Hispanic | 11.4% | 8.7% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Plainville, CT | Vernal, UT | United States |
| Married Population | 43.2% | 47.0% | 49.8% |
| Currently Married | 42.4% | 45.4% | 48.0% |
| Married but Separated | 0.8% | 1.7% | 1.8% |
| Single Population | 56.8% | 53.0% | 50.2% |
| Never Married | 36.5% | 31.9% | 33.8% |
| Divorced | 13.7% | 17.6% | 10.8% |
| Widowed | 6.6% | 3.4% | 5.6% |
| space5 | | | |
| Household Size | 2.17 | 3.01 | 2.60 |
| Households | 7,984 | 3,217 | 124,010,992 |
| Family Households | 4,177 | 2,095 | 80,755,759 |
| Married couple, w/children | 25.1% | 48.4% | 30.5% |
| Married couple, no children | 44.5% | 22.8% | 42.9% |
| Non Family Households | 3,807 | 1,122 | 43,255,233 |
| Single householder, w/children | 15.4% | 13.9% | 15.8% |
| Single householder, no children | 15.0% | 14.8% | 10.8% |