 Those of Hispanic or Latino origin made up 20.2% of the population.In terms of ancestry, 25.6% were German, 13.7% were Irish, 9.2% were English, 8.6% were American, 7.7% were Italian, 7.1% were Swedish, and 5.0% were Polish.Of the 18,505 households, 41.5% had children under the age of 18 living with them, 61.6% were married couples living together, 10.2% had a female householder with no husband present, 22.9% were non-families, and 18.9% of all households were made up of individuals.