 There were 18,735 housing units at an average density of .The racial makeup of the county was 88.5% white, 1.0% American Indian, 1.0% black or African American, 0.8% Asian, 0.1% Pacific islander, 6.4% from other races, and 2.3% from two or more races.Those of Hispanic or Latino origin made up 15.3% of the population.