sentences:  In terms of ancestry, 27.0% were German, 13.3% were Irish, 9.7% were English, and 8.4% were American.Of the 9,741 households, 31.3% had children under the age of 18 living with them, 56.1% were married couples living together, 9.3% had a female householder with no husband present, 29.7% were non-families, and 24.8% of all households were made up of individuals.The average household size was 2.50 and the average family size was 2.96.