 In terms of ancestry, 23.2% were German, 19.2% were English, 15.8% were American, and 12.3% were Irish.Of the 6,495 households, 30.6% had children under the age of 18 living with them, 56.9% were married couples living together, 9.3% had a female householder with no husband present, 29.0% were non-families, and 24.3% of all households were made up of individuals.The average household size was 2.55 and the average family size was 3.01.