February sales at U.S. restaurants open at least 13 months were up 2.7 percent in the United States -- less than the 3.6 percent gain analysts had expected -- and McDonald's shares fell more than 1 percent.
Investor focus has recently shifted toward the U.S. consumer, who has suffered because of high unemployment and now is grappling with higher gas prices, said Oppenheimer analyst Matthew DiFrisco.
Also, the world's largest hamburger chain reported a same-restaurant sales increase of 4.2 percent for the United States in March 2010, boosted by the introduction of McCafe drinks. That high hurdle just makes it harder for the company to post a gain for this month, said DiFrisco.
But Peter Jankovskis, co-chief investment officer at OakBrook Investments, was more optimistic. He attributed the weak U.S. results to severe winter weather that forced multiday business shutdowns in places like the Midwest and said March sales should rebound as a result.
Because U.S. gas prices started rising in late February, Jankovskis said McDonald's results offered scant information on the impact of pricier fuel.
He said he expected higher prices at the pump to hit full-service U.S. restaurants harder than McDonald's because they are more expensive.
It's more likely you'll see a negative impact on casual dining, said Jankovskis. You may see some people who were frequenting those restaurants visit McDonald's instead.
That trade-down should offset the loss of lower-income customers who stop visiting restaurants altogether because of higher gas prices, he said.
Sales in the United States account for about 35 percent of overall revenue.
Spiking prices for gasoline and groceries threaten to cut into consumer spending around the world. At the same time, restaurant operators also are grappling with higher costs for ingredients such as beef, cheese, bread and cooking oil.
In Europe, which contributes about 40 percent of revenue, McDonald's is more of a middle-class draw, DiFrisco said, making restaurant patrons there a bit less sensitive to rising gasoline costs than their U.S. counterparts.
For months, investors have worried that austerity measures would cut into spending in Europe, but same-restaurant sales in that region were up 5.1 percent for a second consecutive month of strong gains after a decline in December. Analysts on average were expecting a rise of 3.6 percent.
Same-restaurant sales rose 4 percent in McDonald's Asia/Pacific, Middle East and Africa unit, better than the 1.8 percent increase analysts expected, with the effects of currency translations slightly dampening the gain.
McDonald's shares were down 1.2 percent at $75.38 in afternoon trading.
(Additional reporting by Phil Wahba in New York, editing by Dave Zimmerman, Maureen Bavdek and Lisa Von Ahn)