• by Sarah Mahoney  @mahoney_sarah, June 3, 2010

As shoppers inch their way toward pre-recession spending levels, they are changing channels again, and May retail results indicate just how elusive defining the "new normal" may be.

Big gainers for the month include warehouse clubs, with Costco's same-store sales up 9% and BJ's Wholesale Clubs up 6.8% -- as well as some luxury retailers, with Neiman Marcus up 7.8% and Saks up 5.8%. Gains were more muted at department stores and specialty apparel companies, and many in the teen sector declined.

"We're seeing the effects of shifts consumers are making among their shopping options," Frank Badillo, senior economist with Kantar Retail, tells Marketing Daily. "Clearly, during the recession Walmart was the beneficiary of those shifts, as middle- and upper-income households traded down toward discount channels. That trend benefited dollar stores as well, and negatively affected other retailers, including Target. Now we're seeing some of that reverse itself," he says.

Target's comparable-store sales rose 1.3% in May, which the company says was somewhat below expectations. And while Walmart does not release monthly results, it recently announced a 1.4% quarterly decline in same-store sales in the U.S., and forecast a further drop in the U.S. of 2% in the coming quarter.

"The battle for these shifting shoppers is going to be key to what happens going forward," Badillo adds. "We still don't know what the 'new normal' is, but I think we're going to see some ongoing bumps in the path of the recovery, including whether the negative fallout from the stock market will affect luxury retail, or whether those who traded down to dollar stores will trade back up to the discount chains."

Kantar's Index, which tracks sales at 30 leading chain stores, gained 2.7% in May -- better than the 1.2% same-store sales gain last month, but "off slightly from the 3.0% to 3.9% trend for the composite that was emerging prior to the Easter-affected months." And the index compiled by the International Council of Shopping Centers, which tracks a slightly different group of stores, gained 2.6% year-over-year.

"The May performance was a bit more uneven than prior months, reflecting the drag that cooler temperatures created on demand for seasonal goods," it said in its release. "However, the 2.6% increase was still a strong showing, especially considering that the shift in the Memorial Day holiday was also a drag on sales, somewhere on the order of 1 percentage point."

For June, ICSC predicts a 3% gain.