| | Sterling, IL | McAllen, TX | United States |
| Population | 14,919 | 141,941 | 329,725,481 |
| Female Population | 48.5% | 50.6% | 50.5% |
| Male Population | 51.5% | 49.4% | 49.5% |
| Median Age | 42.7 | 33 | 38.4 |
| space3 | | | |
| Population - 2010 | 15,412 | 132,104 | 309,327,143 |
| Population - 2000 | 15,451 | 106,414 | 285,036,114 |
| Population - 1990 | 15,132 | 84,021 | 251,960,433 |
| Pop. 2000 to Now | -7.4% | 35.1% | 15.6% |
| Pop. 1990 to Now | -5.4% | 71.1% | 30.8% |
| space4 | | | |
| Population Density | 2,554.6 | 2,159.3 | 93.4 |
| Land Area | 5.8 | 65.7 | 3,531,905.4 |
| Water Area | 0.2 | 0.5 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Sterling, IL | McAllen, TX | United States |
| Age 0 to 4 | 4.2% | 7.2% | 5.9% |
| Age 5 to 9 | 6.5% | 7.9% | 6.1% |
| Age 10 to 14 | 6.0% | 8.5% | 6.6% |
| Age 15 to 17 | 3.5% | 5.4% | 3.9% |
| Age 18 to 20 | 4.4% | 4.1% | 4.0% |
| Age 21 to 24 | 5.8% | 5.5% | 5.2% |
| Age 25 to 34 | 12.2% | 14.1% | 13.8% |
| Age 35 to 44 | 11.8% | 13.8% | 12.9% |
| Age 45 to 54 | 13.1% | 11.8% | 12.6% |
| Age 55 to 59 | 7.0% | 4.6% | 6.7% |
| Age 60 to 64 | 5.2% | 4.2% | 6.3% |
| Age 65 to 74 | 10.5% | 7.6% | 9.6% |
| Age 75 to 84 | 5.8% | 3.9% | 4.5% |
| Age 85 and over | 4.2% | 1.3% | 1.9% |
| space1 | | | |
| Race | | | |
| | Sterling, IL | McAllen, TX | United States |
| White | 67.1% | 8.9% | 59.4% |
| Black | 2.0% | 0.7% | 12.2% |
| Asian | 1.3% | 2.7% | 5.6% |
| Native American | 0.0% | 0.2% | 0.6% |
| Hawaiian, Pacific Islander | 0.1% | 0.0% | 0.2% |
| Other | 0.0% | 0.8% | 0.4% |
| Two or More Races | 3.5% | 0.4% | 3.2% |
| Hispanic | 26.0% | 86.2% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Sterling, IL | McAllen, TX | United States |
| Married Population | 40.8% | 50.1% | 49.8% |
| Currently Married | 38.9% | 47.6% | 48.0% |
| Married but Separated | 1.9% | 2.5% | 1.8% |
| Single Population | 59.2% | 49.9% | 50.2% |
| Never Married | 38.4% | 34.8% | 33.8% |
| Divorced | 12.9% | 9.6% | 10.8% |
| Widowed | 8.0% | 5.5% | 5.6% |
| space5 | | | |
| Household Size | 2.24 | 3.02 | 2.60 |
| Households | 6,467 | 46,679 | 124,010,992 |
| Family Households | 3,698 | 35,095 | 80,755,759 |
| Married couple, w/children | 20.6% | 33.5% | 30.5% |
| Married couple, no children | 40.6% | 31.5% | 42.9% |
| Non Family Households | 2,769 | 11,584 | 43,255,233 |
| Single householder, w/children | 30.0% | 21.0% | 15.8% |
| Single householder, no children | 8.9% | 14.0% | 10.8% |