Chain store sales rose by 2.6% in July over the same period in 2007, according to the International Council of Shopping Centers — a bit of good news amid a plethora of gloomy reports on the weakening U.S. economy.

Discount stores, wholesale clubs and drug stores led the industry in boosting sales, Michael Niemira, ICSC’s chief economist and director of research, noted in a report released on Thursday.

"Although July captured some early back-to-school shopping, the month was dominated by clearance sales and discounts," Niemira says. “Value and convenience retailers performed better in July than the industry as a whole.”

July’s gain, however, was not as great as the 4.2% increase reported in June. Still, it was in line with the 2.5% average monthly year-over-year growth rate trend to date in 2008, Niemira says.

August sales are also expected to show an increase over last year, given the demand for back-to-school and fall merchandise. Niemira projects that industry sales will increase by 2% this month.

The ICSC is a trade association that includes 75,000 members in the U.S. and more than 80 other countries. Members include shopping center owners, developers, managers, marketing specialists, investors, lenders and retailers.