Estimate, Median Age by Sex, Total Population (5-year estimate) in Bennett County, SD was 27.00000 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 Bennett County, SD reached a record high of 35.60000 in January of 2009 and a record low of 26.00000 in January of 2021. 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 Bennett County, SD - last updated from the United States Federal Reserve on May of 2024.