McDonald's reported a better-than-expected 1.9 percent increase in global sales at established restaurants in August, helped by stronger sales in Europe.
Sixteen analysts polled by Consensus Metrix expected sales at restaurants open at least 13 months to rise 0.30 percent.
The world's biggest fast-food chain is fighting to boost sales as smaller U.S. rivals Wendy's and Burger King Worldwide launch attractive promotions and attention-grabbing food such as bacon sundaes.
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