| | Sandwich, IL | Willcox, AZ | United States |
| Population | 7,182 | 3,240 | 329,725,481 |
| Female Population | 51.3% | 51.1% | 50.5% |
| Male Population | 48.7% | 48.9% | 49.5% |
| Median Age | 36.5 | 30.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 7,418 | 3,744 | 309,327,143 |
| Population - 2000 | 6,509 | 3,733 | 285,036,114 |
| Population - 1990 | 5,567 | 3,122 | 251,960,433 |
| Pop. 2000 to Now | 13.4% | -6.0% | 15.6% |
| Pop. 1990 to Now | 32.6% | 12.4% | 30.8% |
| space4 | | | |
| Population Density | 1,516.5 | 526.9 | 93.4 |
| Land Area | 4.7 | 6.1 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Sandwich, IL | Willcox, AZ | United States |
| Age 0 to 4 | 7.1% | 6.7% | 5.9% |
| Age 5 to 9 | 7.0% | 9.1% | 6.1% |
| Age 10 to 14 | 7.1% | 6.5% | 6.6% |
| Age 15 to 17 | 3.9% | 2.7% | 3.9% |
| Age 18 to 20 | 4.4% | 3.9% | 4.0% |
| Age 21 to 24 | 7.9% | 6.1% | 5.2% |
| Age 25 to 34 | 10.9% | 21.1% | 13.8% |
| Age 35 to 44 | 15.2% | 10.6% | 12.9% |
| Age 45 to 54 | 9.8% | 8.6% | 12.6% |
| Age 55 to 59 | 4.1% | 5.8% | 6.7% |
| Age 60 to 64 | 5.2% | 4.7% | 6.3% |
| Age 65 to 74 | 10.0% | 9.0% | 9.6% |
| Age 75 to 84 | 5.6% | 4.2% | 4.5% |
| Age 85 and over | 1.8% | 0.9% | 1.9% |
| space1 | | | |
| Race | | | |
| | Sandwich, IL | Willcox, AZ | United States |
| White | 87.4% | 31.4% | 59.4% |
| Black | 0.1% | 0.5% | 12.2% |
| Asian | 1.0% | 0.6% | 5.6% |
| Native American | 0.1% | 1.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 1.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.3% | 2.4% | 3.2% |
| Hispanic | 11.1% | 63.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Sandwich, IL | Willcox, AZ | United States |
| Married Population | 46.4% | 44.4% | 49.8% |
| Currently Married | 45.3% | 42.5% | 48.0% |
| Married but Separated | 1.1% | 1.9% | 1.8% |
| Single Population | 53.6% | 55.6% | 50.2% |
| Never Married | 35.6% | 40.8% | 33.8% |
| Divorced | 11.7% | 9.4% | 10.8% |
| Widowed | 6.3% | 5.4% | 5.6% |
| space5 | | | |
| Household Size | 2.69 | 2.84 | 2.60 |
| Households | 2,606 | 1,135 | 124,010,992 |
| Family Households | 1,632 | 660 | 80,755,759 |
| Married couple, w/children | 36.3% | 29.5% | 30.5% |
| Married couple, no children | 38.8% | 34.2% | 42.9% |
| Non Family Households | 974 | 475 | 43,255,233 |
| Single householder, w/children | 12.4% | 24.5% | 15.8% |
| Single householder, no children | 12.5% | 11.7% | 10.8% |