Estimate, Median Age by Sex, Total Population (5-year estimate) in Kay County, OK was 38.20000 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 Kay County, OK reached a record high of 39.60000 in January of 2011 and a record low of 38.20000 in January of 2022. 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 Kay County, OK - last updated from the United States Federal Reserve on May of 2024.