Estimate, Median Age by Sex, Total Population (5-year estimate) in Grimes County, TX was 40.30000 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 Grimes County, TX reached a record high of 40.70000 in January of 2015 and a record low of 38.70000 in January of 2010. 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 Grimes County, TX - last updated from the United States Federal Reserve on May of 2024.