WASHINGTON -- The U.S. Department of Agriculture’s (USDA) Risk Management Agency announced Nov. 28 that it will update the methodology to set crop insurance premiums, leading to lower insurance premium rates for many corn and soybean producers in the 2012 crop year. The rate adjustment is based on findings of an independent study and peer review process. The study is part of the Risk Management Agency’s ongoing effort to improve the methodology of determining premium rates for crop insurance. . . .