| | Madrid, IA | Milan, MI | United States |
| Population | 2,782 | 6,156 | 329,725,481 |
| Female Population | 49.1% | 54.0% | 50.5% |
| Male Population | 50.9% | 46.0% | 49.5% |
| Median Age | 44.2 | 38.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 2,561 | 5,841 | 309,327,143 |
| Population - 2000 | 2,264 | 4,775 | 285,036,114 |
| Population - 1990 | 2,395 | 4,040 | 251,960,433 |
| Pop. 2000 to Now | 12.6% | 25.9% | 15.6% |
| Pop. 1990 to Now | 6.5% | 48.8% | 30.8% |
| space4 | | | |
| Population Density | 2,272.9 | 1,782.3 | 93.4 |
| Land Area | 1.2 | 3.5 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Madrid, IA | Milan, MI | United States |
| Age 0 to 4 | 5.1% | 5.7% | 5.9% |
| Age 5 to 9 | 4.5% | 7.6% | 6.1% |
| Age 10 to 14 | 5.2% | 8.0% | 6.6% |
| Age 15 to 17 | 4.0% | 5.2% | 3.9% |
| Age 18 to 20 | 3.4% | 3.9% | 4.0% |
| Age 21 to 24 | 2.3% | 4.2% | 5.2% |
| Age 25 to 34 | 14.0% | 11.5% | 13.8% |
| Age 35 to 44 | 12.2% | 14.6% | 12.9% |
| Age 45 to 54 | 12.9% | 14.5% | 12.6% |
| Age 55 to 59 | 6.3% | 4.6% | 6.7% |
| Age 60 to 64 | 8.4% | 4.6% | 6.3% |
| Age 65 to 74 | 11.1% | 11.8% | 9.6% |
| Age 75 to 84 | 5.4% | 2.5% | 4.5% |
| Age 85 and over | 5.2% | 1.4% | 1.9% |
| space1 | | | |
| Race | | | |
| | Madrid, IA | Milan, MI | United States |
| White | 96.3% | 86.7% | 59.4% |
| Black | 0.1% | 3.8% | 12.2% |
| Asian | 0.0% | 0.2% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.2% | 0.4% |
| Two or More Races | 1.0% | 4.8% | 3.2% |
| Hispanic | 2.6% | 4.3% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Madrid, IA | Milan, MI | United States |
| Married Population | 46.9% | 38.8% | 49.8% |
| Currently Married | 46.5% | 38.7% | 48.0% |
| Married but Separated | 0.4% | 0.1% | 1.8% |
| Single Population | 53.1% | 61.2% | 50.2% |
| Never Married | 29.5% | 32.8% | 33.8% |
| Divorced | 14.7% | 20.5% | 10.8% |
| Widowed | 8.9% | 7.8% | 5.6% |
| space5 | | | |
| Household Size | 2.31 | 2.50 | 2.60 |
| Households | 1,174 | 2,454 | 124,010,992 |
| Family Households | 692 | 1,453 | 80,755,759 |
| Married couple, w/children | 18.2% | 32.1% | 30.5% |
| Married couple, no children | 57.1% | 27.4% | 42.9% |
| Non Family Households | 482 | 1,001 | 43,255,233 |
| Single householder, w/children | 17.8% | 21.1% | 15.8% |
| Single householder, no children | 6.9% | 19.4% | 10.8% |