Livestock holdings in counties across the United States were estimated using data from the 1987 Census of Agriculture. The information included the number of milk cows, farms, and the value of livestock in dollars. The estimates were based on surveys of farms that sold or would have sold at least $1,000 worth of agricultural products in the census year. The data mainly represented 1987, with some details from the 1982 census included. The county boundaries and non-land features were derived from digital maps.