For McDonald's Corp., this will be a year built on new kinds of beef, breakfast, beverages and McBites, as the restaurant chain attempts to erase last year's sales struggles. The company's 14,000-plus domestic restaurants, representing roughly half of all operations, offered some new products in 2012, but most of them failed to reproduce the success McDonald's had in past years with Angus burgers and snack wraps. That contributed to lower sales, a stock price that sagged 12 percent over the year and the departure of the head of U.S. operations. Now, Chief Operating Officer Tim Fenton is promising a "more robust" pipeline of new products from the Oak Brook-based company, including items that have been hits in other markets. Menu changes are the "crux of McDonald's success," says R.J. Hottovy, an analyst at Morningstar Inc. in Chicago. "They missed opportunities to introduce new premium products last year. That's the ultimate thing we have to see from McDonald's this year."