DES MOINES — A new survey suggests that farmland values in Iowa have inched upward in the past six months. A report from the Iowa Realtors Land Institute Chapter No. 2 says the farmland values climbed nearly 1 percent from September to March, hitting $6,545 an acre. The increase was the first since September 2013. The report says, however, that farmland values are still 2.8 percent lower for the past 12 months. The institute’s surveys suggest that the average value of Iowa’s farmland has dropped about 25 percent since March 2013.