| | Arroyo Seco, NM | Alamosa, CO | United States |
| Population | 2,399 | 9,704 | 329,725,481 |
| Female Population | 60.3% | 50.1% | 50.5% |
| Male Population | 39.7% | 49.9% | 49.5% |
| Median Age | 40.3 | 28.7 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,903 | 8,907 | 309,327,143 |
| Population - 2000 | 1,686 | 7,960 | 285,036,114 |
| Population - 1990 | 1,213 | 7,579 | 251,960,433 |
| Pop. 2000 to Now | -23.3% | 17.7% | 15.6% |
| Pop. 1990 to Now | 6.7% | 23.6% | 30.8% |
| space4 | | | |
| Population Density | 351.5 | 1,304.0 | 93.4 |
| Land Area | 6.8 | 7.4 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Arroyo Seco, NM | Alamosa, CO | United States |
| Age 0 to 4 | 2.1% | 6.5% | 5.9% |
| Age 5 to 9 | 12.0% | 5.1% | 6.1% |
| Age 10 to 14 | 2.5% | 8.8% | 6.6% |
| Age 15 to 17 | 0.0% | 3.9% | 3.9% |
| Age 18 to 20 | 0.0% | 10.8% | 4.0% |
| Age 21 to 24 | 6.5% | 9.7% | 5.2% |
| Age 25 to 34 | 23.8% | 14.5% | 13.8% |
| Age 35 to 44 | 12.0% | 13.1% | 12.9% |
| Age 45 to 54 | 0.0% | 7.5% | 12.6% |
| Age 55 to 59 | 10.5% | 4.8% | 6.7% |
| Age 60 to 64 | 8.5% | 5.3% | 6.3% |
| Age 65 to 74 | 18.0% | 6.4% | 9.6% |
| Age 75 to 84 | 2.2% | 2.2% | 4.5% |
| Age 85 and over | 1.9% | 1.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | Arroyo Seco, NM | Alamosa, CO | United States |
| White | 19.5% | 37.2% | 59.4% |
| Black | 0.0% | 0.8% | 12.2% |
| Asian | 0.0% | 1.6% | 5.6% |
| Native American | 0.0% | 0.4% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.1% | 0.2% |
| Other | 0.0% | 0.6% | 0.4% |
| Two or More Races | 0.0% | 3.1% | 3.2% |
| Hispanic | 80.5% | 56.3% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Arroyo Seco, NM | Alamosa, CO | United States |
| Married Population | 26.7% | 36.2% | 49.8% |
| Currently Married | 26.7% | 35.1% | 48.0% |
| Married but Separated | 0.0% | 1.1% | 1.8% |
| Single Population | 73.3% | 63.8% | 50.2% |
| Never Married | 52.9% | 46.2% | 33.8% |
| Divorced | 15.5% | 13.5% | 10.8% |
| Widowed | 4.8% | 4.0% | 5.6% |
| space5 | | | |
| Household Size | 4.14 | 2.24 | 2.60 |
| Households | 579 | 3,956 | 124,010,992 |
| Family Households | 345 | 2,009 | 80,755,759 |
| Married couple, w/children | 8.1% | 35.2% | 30.5% |
| Married couple, no children | 31.0% | 31.9% | 42.9% |
| Non Family Households | 234 | 1,947 | 43,255,233 |
| Single householder, w/children | 10.7% | 20.5% | 15.8% |
| Single householder, no children | 50.1% | 12.4% | 10.8% |