2005 52,061 2000 46,107 1990 38,147 1980 36,446 1970 30,870 1960 27,543 1950 23,993 1940 22,081 1930 22,290 1920 23,575 1910 24,673 1900 26,321 1890 26,572 1880 25,922 1870 22,593 1860 16,753 1850 11,631 1840 8,121 1830 621
As of the census of 2000, there were 46,107 people, 17,081 households, and 12,810 families residing in the county. The population density was 109 people per square mile (42/km²). There were 17,929 housing units at an average density of 42 per square mile (16/km²). The racial makeup of the county was 97.92% White, 0.35% Black or African American, 0.26% Native American, 0.46% Asian, 0.01% Pacific Islander, 0.40% from other races, and 0.60% from two or more races. 1.16% of the population were Hispanic or Latino of any race. 28.3% were of German, 19.6% American, 12.7% English and 9.6% Irish ancestry according to Census 2000.
There were 17,081 households out of which 38.00% had children under the age of 18 living with them, 64.40% were married couples living together, 7.80% had a female householder with no husband present, and 25.00% were non-families. 21.10% of all households were made up of individuals and 8.60% had someone living alone who was 65 years of age or older. The average household size was 2.65 and the average family size was 3.09.
In the county the population was spread out with 28.30% under the age of 18, 6.30% from 18 to 24, 30.20% from 25 to 44, 23.40% from 45 to 64, and 11.80% who were 65 years of age or older. The median age was 37 years. For every 100 females there were 95.40 males. For every 100 females age 18 and over, there were 90.90 males.
The median income for a household in the county was $49,632, and the median income for a family was $58,879. Males had a median income of $39,534 versus $26,266 for females. The per capita income for the county was $24,182. About 3.80% of families and 5.20% of the population were below the poverty line, including 4.80% of those under age 18 and 9.00% of those age 65 or over.