Shoppers searched for bargains and basics in May, leading several retailers to miss sales expectations on Thursday even though the bar was set pretty low for most chains.

While there have been early signs of stabilization such as improving consumer confidence, issues such as unemployment and the troubled housing market have led many Americans to take on a thriftier attitude.

At Costco Wholesale Corp same-store sales fell 7 percent, worse than analysts' expected, hurt by the stronger U.S. dollar and lower gasoline prices, which deflated its fuel sales.

Costco is now the largest member of the revenue-weighted Thomson Reuters same-store sales index since Wal-Mart Stores Inc decided to no longer report monthly sales. Wal-Mart, the world's largest retailer, had accounted for about half of the Thomson Reuters index.

So far, seven of 12 retailers have reported worse-than-expected same-store sales, or sales at stores open at least a year, according to Thomson Reuters data.

Overall, May same-store sales were expected to fall 4.1 percent from a year earlier at companies tracked by Thomson Reuters, compared with a 1.1 percent rise in May 2008. Such a decline would be smaller than the year-to-date average of a 4.5 percent drop.

In May 2008, before the financial crisis was declared a recession, retailers felt the benefit of consumers starting to spend their stimulus rebate checks.

FOOD SELLS AT COSTCO

Excluding sales of gasoline, Costco's same-store sales rose 1 percent. Food was one of the best sellers, with shoppers scooping up deli meats, frozen food and candy. While electronics sold well, average prices in the category were down 39 percent, the company said.

In the teen category, Hot Topic Inc said late on Wednesday that its same-store sales fell 6.4 percent in May, steeper than analysts' forecast for a 4.3 percent decline.

One bright spot was Buckle Inc , which surpassed forecasts with a 13.4 percent jump in May same-store sales.

Results from smaller retailers such as Buckle may receive more attention now that Wal-Mart has stopped reporting monthly sales, analysts said.

Without Wal-Mart's impact, investors will get a clearer picture of how other discount chains, department stores, apparel retailers and drugstores are faring in the recession.

At Buckle, which caters to teens with more basic merchandise, women's and men's denim and accessories sold well. Buckle said it even sold some more expensive items than a year earlier, with prices up about 3 percent in the women's category, which accounts for the majority of its business, and up about 8 percent on the men's side.

While Wal-Mart did not issue monthly sales data, investors will watch for any general comments it makes about sales as it talks to members of the media on Thursday and addresses shareholders and analysts at meetings on Friday.

(Additional reporting by Martinne Geller in New York, editing by Dave Zimmerman)

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