The bad news just keeps piling on at J.C. Penney Co. The chain reported a third-quarter loss of 56 cents per share, or $123 million, on revenue that plunged 26 percent in the latest sign that customers are not happy the retailer ditched hundreds of coupons and big sales it offered each year in favor of everyday low pricing. It is the third consecutive quarter of losses and steep sales declines that Plano, Texas-based Penney has reported since the change. The results underscore the challenges chief executive Ron Johnson faces as he attempts to change the way people shop. The year-ago loss was $143 million, or 67 cents per share.