| | Flat Rock, MI | Cadillac, MI | United States |
| Population | 10,439 | 10,317 | 329,725,481 |
| Female Population | 49.1% | 50.2% | 50.5% |
| Male Population | 50.9% | 49.8% | 49.5% |
| Median Age | 36.7 | 39.7 | 38.4 |
| space3 | | | |
| Population - 2010 | 9,868 | 10,354 | 309,327,143 |
| Population - 2000 | 8,488 | 10,000 | 285,036,114 |
| Population - 1990 | 7,290 | 10,104 | 251,960,433 |
| Pop. 2000 to Now | 17.3% | 5.2% | 15.6% |
| Pop. 1990 to Now | 36.6% | 4.1% | 30.8% |
| space4 | | | |
| Population Density | 1,594.7 | 1,462.4 | 93.4 |
| Land Area | 6.5 | 7.1 | 3,531,905.4 |
| Water Area | 0.2 | 1.9 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Flat Rock, MI | Cadillac, MI | United States |
| Age 0 to 4 | 5.7% | 6.8% | 5.9% |
| Age 5 to 9 | 7.4% | 7.0% | 6.1% |
| Age 10 to 14 | 8.0% | 4.7% | 6.6% |
| Age 15 to 17 | 5.7% | 2.6% | 3.9% |
| Age 18 to 20 | 2.7% | 1.4% | 4.0% |
| Age 21 to 24 | 5.2% | 5.5% | 5.2% |
| Age 25 to 34 | 12.4% | 15.5% | 13.8% |
| Age 35 to 44 | 15.4% | 11.6% | 12.9% |
| Age 45 to 54 | 11.3% | 12.0% | 12.6% |
| Age 55 to 59 | 7.5% | 4.3% | 6.7% |
| Age 60 to 64 | 7.3% | 8.6% | 6.3% |
| Age 65 to 74 | 9.1% | 11.2% | 9.6% |
| Age 75 to 84 | 1.3% | 4.6% | 4.5% |
| Age 85 and over | 1.0% | 4.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | Flat Rock, MI | Cadillac, MI | United States |
| White | 77.7% | 93.9% | 59.4% |
| Black | 10.1% | 1.7% | 12.2% |
| Asian | 0.1% | 0.0% | 5.6% |
| Native American | 0.3% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 3.2% | 2.3% | 3.2% |
| Hispanic | 8.7% | 2.1% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Flat Rock, MI | Cadillac, MI | United States |
| Married Population | 48.5% | 43.6% | 49.8% |
| Currently Married | 47.0% | 41.4% | 48.0% |
| Married but Separated | 1.5% | 2.2% | 1.8% |
| Single Population | 51.5% | 56.4% | 50.2% |
| Never Married | 37.0% | 31.2% | 33.8% |
| Divorced | 10.1% | 16.8% | 10.8% |
| Widowed | 4.4% | 8.4% | 5.6% |
| space5 | | | |
| Household Size | 2.79 | 2.29 | 2.60 |
| Households | 3,738 | 4,430 | 124,010,992 |
| Family Households | 2,746 | 2,372 | 80,755,759 |
| Married couple, w/children | 31.0% | 23.3% | 30.5% |
| Married couple, no children | 37.1% | 44.1% | 42.9% |
| Non Family Households | 992 | 2,058 | 43,255,233 |
| Single householder, w/children | 20.9% | 18.9% | 15.8% |
| Single householder, no children | 11.0% | 13.8% | 10.8% |