Estimate, Median Age by Sex, Total Population (5-year estimate) in Harrison County, MO was 42.20000 Years of Age in January of 2022, according to the United States Federal Reserve. Historically, Estimate, Median Age by Sex, Total Population (5-year estimate) in Harrison County, MO reached a record high of 43.50000 in January of 2010 and a record low of 42.10000 in January of 2014. Trading Economics provides the current actual value, an historical data chart and related indicators for Estimate, Median Age by Sex, Total Population (5-year estimate) in Harrison County, MO - last updated from the United States Federal Reserve on May of 2024.