From department stores to discounters, the nation's retailers reported sluggish August sales yesterday as consumers cut back spending during the generally lucrative back-to-school shopping month.

The figures, the worst in 17 months, are the result of higher gasoline prices, tepid consumer confidence and a later-than-usual Labor Day, which pushed the big purchasing weekend into September, analysts said.

The International Council of Shopping Centers, which tracks 71 chain stores, said same-store sales rose a modest 1.1 percent, falling short of the group's forecast of a 1.5 to 2 percent increase.

"There was weakness in every segment," said Michael P. Niemira, chief economist at the New York-based shopping center organization.

Wall Street appeared to take the retail numbers in stride, predicting a stronger September. The stock price of several retailers rose even as the companies reported declining sales.

Discounter Wal-Mart Stores Inc., the nation's largest retailer and an industry bellwether, suffered its poorest performance in 31/2 years, with sales up just 0.5 percent.

Target Corp. of Minneapolis, the No. 2 discounter, fared better. It said August same-store sales rose 1.8 percent, beating analysts' predictions of a 1.2 percent increase.

At the high end of retail, Neiman Marcus, Nordstrom and Saks Fifth Avenue reported strong gains in August, with their shoppers insulated from higher food and gas prices, analysts said.

"The low-end consumer is still struggling," said Bill Dreher, an analyst at Deutsche Bank Securities Inc.

Same-store sales offer the most accurate retail figures because they exclude results from new and closed locations.

The August-September back-to-school period is the retail industry's second-biggest shopping season behind the Christmas holiday buying binge.

Retailers pointed out that this August's sales were being measured against the period last year when consumers were receiving federal child-tax-credit checks and being urged to spend them.

Bentonville, Ark.-based Wal-Mart, in a statement, called it the "toughest sales comparison we will face this year."

For the most part, mid-priced department stores reported dismal sales.

St. Louis-based May Department Stores Co., owner of Lord & Taylor, Filene's and Hecht's, reported that same-store sales fell 6.7 percent for the month. Federated Department Stores Inc., the Cincinnati-based owner of Macy's, Bloomingdale's and Lazarus, said sales were down 2.4 percent. And Sears, Roebuck and Co. of Hoffman Estates, Ill., said sales fell 6.1 percent.

One bright spot among mid-range stores was J.C. Penney. Same-store sales for the Plano, Tex.-based chain rose 4.1 percent.

Several high-end department stores surpassed analysts' expectations. Same-store sales jumped 7.2 percent at Seattle-based Nordstrom Inc. and 14.7 percent at the Neiman Marcus Group of Dallas.

"They don't do a lot of back-to-school business," said Jeff Stinson, an analyst at FTN Midwest Research Securities Corp. "They tend to market to older, affluent shoppers."

Hannah Poole, left, and Amanda Schlitzer shop at a suburban Philadelphia store. A later-than-usual Labor Day may have pushed many back-to-school purchases into September, reducing August retail sales, analysts say.