SHAKE-UP: McDonald's Corp. is replacing the head of its U.S. business after the world's biggest hamburger chain reported the first drop in a monthly sales figure in nearly a decade.

COMING AND GOING: The company says Jan Fields, president of McDonald's USA, will be replaced by its global chief restaurant officer, Jeff Stratton, as of Dec. 1.

TOUGH TIMES: After years of outperforming its rivals, McDonald's is facing stiffer competition from chains such as Burger King and Wendy's that are undergoing turnaround efforts. Customers are also flocking to restaurants such as Chipotle Mexican Grill and Panera Bread Co. that offer better quality food for slightly higher prices.