 2.66% of the population were Hispanic or Latino of any race.39.6% were of German, 12.6% Norwegian, 8.3% Irish and 5.1% Swedish ancestry.There were 30,692 households, of which 45.40% had children under the age of 18 living with them, 66.90% were married couples living together, 7.40% had a female householder with no husband present, and 21.90% were non-families.