2000 115,209 1990 88,109 1980 77,240 1970 61,138 1960 43,704 1950 26,183 1940 22,493 1930 21,706 1920 20,739 1910 20,394 1900 20,223 1890 19,561 1880 19,537 1870 18,366 1860 14,854 1850 12,101 1840 9,352 1830 4,019
As of the census of 2000, there were 115,209 people, 42,434 households, and 31,613 families residing in the county. The population density was 360 people per square mile (139/km²). There were 45,095 housing units at an average density of 141 per square mile (54/km²). The racial makeup of the county was 97.04% White, 0.79% Black or African American, 0.18% Native American, 0.84% Asian, 0.03% Pacific Islander, 0.48% from other races, and 0.65% from two or more races. 1.38% of the population were Hispanic or Latino of any race. 26.5% were of German, 19.6% American, 12.4% English and 10.9% Irish ancestry according to Census 2000.
There were 42,434 households out of which 37.40% had children under the age of 18 living with them, 62.00% were married couples living together, 9.00% had a female householder with no husband present, and 25.50% were non-families. 21.20% of all households were made up of individuals and 7.30% had someone living alone who was 65 years of age or older. The average household size was 2.63 and the average family size was 3.06.
In the county the population was spread out with 27.20% under the age of 18, 8.70% from 18 to 24, 30.80% from 25 to 44, 22.30% from 45 to 64, and 11.00% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 96.00 males. For every 100 females age 18 and over, there were 92.80 males.
The median income for a household in the county was $52,693, and the median income for a family was $60,571. Males had a median income of $42,272 versus $28,181 for females. The per capita income for the county was $22,976. About 3.30% of families and 5.60% of the population were below the poverty line, including 5.70% of those under age 18 and 7.70% of those age 65 or over.