Warehouse club operator Costco Wholesale reported a decline in quarterly comparable sales and lower-than-expected sales, hurt by gasoline price deflation and a stronger dollar that reduced value of sales from overseas markets.
Shares of the third-largest U.S. retailer were down slightly at $144.95 in after-market trading on Wednesday.
Comparable sales at outlets open more than one year declined 1 percent in the quarter, including fuel and foreign currency impacts. This was below the 0.7 percent growth expected by analysts polled by research firm Consensus Metrix.
Excluding the impact of fuel prices and currency, comparable sales rose 6 percent, still missing analysts' estimates of 6.20 percent growth.
Rival Wal-Mart Stores reported quarterly sales and earnings below analysts' estimates last week, saying consumers spent less of their savings from the pump and tax refunds.
Costco sells gas at a lower margin, in order to attract more customers to its stores who then spend on higher-margin goods.
Net income attributable to the company rose to $516 million, or $1.17 per share, in the third quarter ended May 10 from $473 million, or $1.07 per share, a year earlier.
Revenue rose 1 percent to $25.52 billion.
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Analysts on average had expected a profit of $1.15 per share and revenue of $26.63 billion, according to Thomson Reuters I/B/E/S.
Shares of Costco, the third-largest U.S. retailer closed at $145.42 on the Nasdaq on Wednesday. Up to Wednesday's close, the stock had risen nearly 6 percent this year.