2000 census As of the census of 2000, there were 20,255 people, 8,055 households, and 5,557 families residing in the city. The population density was . There were 8,310 housing units at an average density of . The racial makeup of the city was 97.44% White, 0.54% African American, 0.16% Native American, 0.97% Asian, 0.01% Pacific Islander, 0.15% from other races, and 0.73% from two or more races. Hispanic or Latino of any race were 0.70% of the population. 17.1% were of German, 16.4% Italian, 15.1% Irish, 7.5% Polish, 6.1% Slovene and 5.7% English ancestry according to Census 2000.
2000 census As of the census of 2000, there were 20,255 people, 8,055 households, and 5,557 families residing in the city. The population density was  There were 8,310 housing units at an average density of . The racial makeup of the city was 97.44% White, 0.54% African American, 0.16% Native American, 0.97% Asian, 0.01% Pacific Islander, 0.15% from other races, and 0.73% from two or more races. Hispanic or Latino of any race were 0.70% of the population. 17.1% were of German, 16.4% Italian, 15.1% Irish, 7.5% Polish, 6.1% Slovene and 5.7% English ancestry according to Census 2000.