| | Adair, IA | Lamoni, IA | United States |
| Population | 856 | 2,285 | 329,725,481 |
| Female Population | 50.5% | 47.6% | 50.5% |
| Male Population | 49.5% | 52.4% | 49.5% |
| Median Age | 37.7 | 27.7 | 38.4 |
| space3 | | | |
| Population - 2010 | 781 | 2,327 | 309,327,143 |
| Population - 2000 | 839 | 2,444 | 285,036,114 |
| Population - 1990 | 894 | 2,319 | 251,960,433 |
| Pop. 2000 to Now | -16.5% | -10.2% | 15.6% |
| Pop. 1990 to Now | -21.6% | -5.3% | 30.8% |
| space4 | | | |
| Population Density | 389.4 | 577.3 | 93.4 |
| Land Area | 2.2 | 4.0 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Adair, IA | Lamoni, IA | United States |
| Age 0 to 4 | 7.0% | 3.3% | 5.9% |
| Age 5 to 9 | 11.4% | 4.2% | 6.1% |
| Age 10 to 14 | 3.0% | 3.9% | 6.6% |
| Age 15 to 17 | 2.6% | 2.2% | 3.9% |
| Age 18 to 20 | 1.5% | 24.0% | 4.0% |
| Age 21 to 24 | 5.5% | 10.8% | 5.2% |
| Age 25 to 34 | 15.4% | 9.5% | 13.8% |
| Age 35 to 44 | 9.5% | 6.5% | 12.9% |
| Age 45 to 54 | 12.7% | 6.6% | 12.6% |
| Age 55 to 59 | 8.3% | 5.6% | 6.7% |
| Age 60 to 64 | 6.2% | 6.0% | 6.3% |
| Age 65 to 74 | 7.5% | 8.3% | 9.6% |
| Age 75 to 84 | 7.4% | 6.7% | 4.5% |
| Age 85 and over | 2.0% | 2.5% | 1.9% |
| space1 | | | |
| Race | | | |
| | Adair, IA | Lamoni, IA | United States |
| White | 86.7% | 80.4% | 59.4% |
| Black | 2.1% | 5.2% | 12.2% |
| Asian | 5.8% | 1.7% | 5.6% |
| Native American | 0.0% | 0.2% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 2.6% | 6.7% | 3.2% |
| Hispanic | 2.8% | 5.8% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Adair, IA | Lamoni, IA | United States |
| Married Population | 52.7% | 41.5% | 49.8% |
| Currently Married | 51.9% | 40.9% | 48.0% |
| Married but Separated | 0.7% | 0.6% | 1.8% |
| Single Population | 47.3% | 58.5% | 50.2% |
| Never Married | 24.4% | 46.8% | 33.8% |
| Divorced | 14.1% | 6.2% | 10.8% |
| Widowed | 8.8% | 5.6% | 5.6% |
| space5 | | | |
| Household Size | 2.48 | 2.02 | 2.60 |
| Households | 344 | 849 | 124,010,992 |
| Family Households | 197 | 483 | 80,755,759 |
| Married couple, w/children | 33.5% | 26.5% | 30.5% |
| Married couple, no children | 50.8% | 52.8% | 42.9% |
| Non Family Households | 147 | 366 | 43,255,233 |
| Single householder, w/children | 11.7% | 10.8% | 15.8% |
| Single householder, no children | 4.1% | 9.9% | 10.8% |