 The average household size was 3.11 and the average family size was 3.45.The county population contained 31.20% under the age of 18, 20.60% from 18 to 24, 23.60% from 25 to 44, 16.10% from 45 to 64, and 8.60% who were 65 years of age or older.The median age was 24 years.