OAK BROOK, Ill. (AP) — McDonald's Corp. said Tuesday that a key revenue figure rose in April as strength in the U.S. and U.K. helped offset weakness in Japan. But the results missed analysts' expectations, and its shares slipped in morning trading.

Although McDonald's has consistently outperformed its rivals, the chain is facing the same pressures from the turbulent global economy as well as rising commodity costs that are hitting the entire industry. Its sales figures came as rival Wendy's Co. reported first quarter results that missed expectations on higher costs for ingredients like beef and lower than expected sales.

McDonald's CEO Jim Skinner said in a statement the chains evolving menu and revamped stores will help meet customers' needs "amidst a challenging global economy."

The world's largest hamburger chain says global sales rose 3.3 percent at stores open at least 13 months in April. But Thomson Reuters says analysts expected a 4.1 percent rise and McDonald's, based in Oak Brook, Ill., had forecast a 4 percent rise.

The figure is a key metric because it excludes the impact of newly opened or closed stores.

The figure rose 3.3 percent in the U.S., boosted by its new extra value meal offerings like a 20-pice Chicken McNuggets. New drinks and breakfast offerings were also popular.

The sales figure rose 3.5 percent in Europe on strength in France, the U.K., Germany and Russia. The Monopoly game was popular in Germany and the U.K. and 1.1 percent in Asia/Pacific, the Middle East and Africa. McDonald's says positive results in China were offset by negative results in Japan.

Year to date, sales at stores open at least 13 months is up 6.2 percent, including a 7.4 percent rise in the U.S., 4.6 percent rise in Europe and 4.3 percent rise in Asia/Pacific, the Middle East and Africa.

Shares fell 76 cents to $94.75 in morning trading. The stock had been down 5 percent since the beginning of the year.