2007–2011 Census data showed 19.2% of Carthage residents were under the age of 18, while 22.6% of the population was over the age of 65. The median age in Carthage was 44.0 years, and there were 88.3 males for every 100 females. Of residents over the age of 15, 50.8% of persons were married. Of persons over the age of 25, 93.2% had earned at least a high school diploma while 19.2% had earned a bachelor's degree or higher. 7.2% of persons held a graduate degree.