sentences:  In terms of ancestry, 26.3% were German, 16.8% were American, 15.1% were English, and 13.4% were Irish.Of the 6,639 households, 30.3% had children under the age of 18 living with them, 54.5% were married couples living together, 9.0% had a female householder with no husband present, 31.8% were non-families, and 27.8% of all households were made up of individuals.The average household size was 2.38 and the average family size was 2.87.