Gallup is located in Mckinley county New mexico with a geographic area of 20.2 square miles. The total population in Gallup is 21,637 with 48.4% male and 51.6% female. Children under age 5 represent 7.9% of the population, under age 18 equal 31.2% of the population and over age 65 is 13.3% of the population. The median household income is $45,754, per capita income is $21,231. There are a total of 7,499 housing units with 51.0% owner occupied. Education includes 34.7% of residents that are high school graduates and 23.4% with a bachelor's degree or higher. The average temperature in Gallup in the summer is 67 degrees, and in the winter 32 degrees.