Return of the Mac

McDonald’s says new Big Mac sizes helped boost a key sales figure in the U.S., its flagship market where the fast-food chain has suffered years of falling customer visits.

Worldwide, McDonald’s said sales at stores open at least 13 months rose 4 percent. Sales can also increase as a result of higher prices or by people buying more expensive items and the company says it’s still working on trying to attract more customers to its stores.

Efforts to improve the image of its food have included a recent announcement that it will start using fresh instead of frozen beef for its Quarter Pounders next year. It’s also promoting a bigger version of its Big Mac called the “Grand Mac,” as well as a smaller version called “Mac Jr.”

The company’s first quarter profit and sales were better than expected, and its stock, which had reached all-time highs in recent days, gained 5.6 percent to $141.70.