Benton County is part of the Lafayette, Indiana Metropolitan Statistical Area.
2000 9,421 1990 9,441 1980 10,218 1970 11,262 1960 11,912 1950 11,462 1940 11,117 1930 11,886 1920 12,206 1910 12,688 1900 13,123 1890 11,903 1880 11,108 1870 5,615 1860 2,809 1850 1,144
As of the census of 2000, there were 9,421 people, 3,558 households, and 2,547 families residing in the county. The population density was 23 people per square mile (9/km²). There were 3,818 housing units at an average density of 9 per square mile (4/km²). The racial makeup of the county was 96.90% White, 0.21% Black or African American, 0.14% Native American, 0.08% Asian, 1.28% from other races, and 1.38% from two or more races. 2.60% of the population were Hispanic or Latino of any race. 33.8% were of German, 20.3% American, 10.7% Irish, 6.8% English and 6.1% French ancestry according to Census 2000.
There were 3,558 households out of which 35.20% had children under the age of 18 living with them, 59.50% were married couples living together, 8.50% had a female householder with no husband present, and 28.40% were non-families. 24.50% of all households were made up of individuals and 12.80% had someone living alone who was 65 years of age or older. The average household size was 2.59 and the average family size was 3.09.
In the county the population was spread out with 27.90% under the age of 18, 7.10% from 18 to 24, 27.80% from 25 to 44, 21.50% from 45 to 64, and 15.70% who were 65 years of age or older. The median age was 37 years. For every 100 females there were 98.60 males. For every 100 females age 18 and over, there were 92.10 males.
The median income for a household in the county was $39,813, and the median income for a family was $46,869. Males had a median income of $30,592 versus $22,169 for females. The per capita income for the county was $17,220. About 3.50% of families and 5.50% of the population were below the poverty line, including 6.00% of those under age 18 and 4.50% of those age 65 or over.