Agricultural Land Values Highlights. The United States farm real estate value, a measurement of the value of all land and buildings on farms, averaged $3,020 per acre for 2015, up 2.4 percent from 2014 values.he United States cropland value increased by $30 per acre (0.7 percent) to $4,130 per acre from the previous year. In the Southern Plains region, the average cropland value increased 9.2 percent from the previous year.