Estimate, Median Age by Sex, Total Population (5-year estimate) in Clark County, SD was 41.20000 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 Clark County, SD reached a record high of 46.20000 in January of 2009 and a record low of 40.30000 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 Clark County, SD - last updated from the United States Federal Reserve on May of 2024.