Calhoun County is a county in the U.S. state of Michigan. As of the 2010 census, the population was 136,146. The county seat is Marshall. The county was established on October 19, 1829 and named after John C. Calhoun, who was at the time Vice President under Andrew Jackson, making it one of Michigan’s Cabinet counties. County government was first organized on March 6, 1833.
According to the U.S. Census Bureau, the county has a total area of 718 square miles (1,860 km), of which 706 square miles (1,830 km) is land and 12 square miles (31 km) (1.7%) is water.
The 2010 United States Census indicates Calhoun County had a 2010 population of 136,146. This is a decrease of -1,839 people from the 2000 United States Census. Overall, the county had a -1.3% growth rate during this ten-year period. In 2010 there were 54,016 households and 35,220 families in the county. The population density was 192.8 per square mile (74.4 square kilometers). There were 61,042 housing units at an average density of 86.4 per square mile (33.4 square kilometers). The racial and ethnic makeup of the county was 79.8% White, 10.7% Black or African American, 0.5% Native American, 1.6% Asian, 4.5% Hispanic or Latino, 0.1% from other races, and 2.7% from two or more races.
There were 54,016 households out of which 31.2% had children under the age of 18 living with them, 45.3% were husband and wife families, 14.6% had a female householder with no husband present, 34.8% were non-families, and 28.8% were made up of individuals. The average household size was 2.44 and the average family size was 2.98.
In the county, the population was spread out with 24.2% under age of 18, 9.3% from 18 to 24, 24.0% from 25 to 44, 27.7% from 45 to 64, and 14.8% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 95.5 males. For every 100 females age 18 and over, there were 92.5 males.
The 2010 American Community Survey 1-year estimate indicates the median income for a household in the county was $42,921 and the median income for a family was $49,964. Males had a median income of $25,712 versus $18,298 for females. The per capita income for the county was $20,661. About 11.7% of families and 16.2% of the population were below the poverty line, including 23.9% of those under the age 18 and 5.8% of those age 65 or over.