Residents in the Warsaw area and other customers of Summit Natural Gas will soon notice a change in their annual gas rates but not as much as originally thought. The Missouri Public Service commission is correcting a calculation error made last month regarding a purchased gas adjustment change. Staff with the P.S.C. say the corrected numbers indicate a smaller annual rate increase for residential customers. Estimates show that customers in Warsaw will see an annual increase in their total natural gas bill under normal weather conditions of $358 instead of the originally projected amount of $520. The new rates go into effect next month.