Wendy's said same-restaurant sales rose 3.2 percent in the quarter ended March 29. Analysts on average had expected a 2.5 percent rise, according to Consensus Metrix.
The company also raised the number of U.S. restaurants it plans to sell to franchisees this year to 280 from 225.
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Wendy's, like other burger chains including McDonald's and Burger King, has been selling many company-owned restaurants to franchisees to cut costs and boost cash flow and margins.
Wendy's sold 240 restaurants to franchisees in the first quarter.
The company's net income fell to $27.5 million, or 7 cents per share, from $46.3 million, or 12 cents per share, a year earlier, due to the sale of restaurants.
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Excluding items, Wendy's earned 6 cents per share.
Total sales fell about 11 percent to $466.2 million.