Resident Population in Clark County, OH was 134.61000 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Clark County, OH reached a record high of 160.00000 in January of 1971 and a record low of 134.31500 in January of 2019. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Clark County, OH - last updated from the United States Federal Reserve on May of 2024.