Back-to-school boosts mass merchants' August sales

Retailers reporting monthly sales for August were lifted by back-to-school shopping and posted a 2.9 percent gain year-over-year on a comparable-store basis, a according to the International Council of Shopping Centers (ICSC).

The performance was an improvement from the ICSC’s July tally -- a 2.6 percent year-over-year increase.

"In August, sales picked-up a tad, but clearly the economic environment remains challenging for retailers," said Michael Niemira, ICSC's chief economist and director of research. "With continuing housing market problems, consumer spending trends will likely remain subdued in the foreseeable future," Niemira added.

Wal-Mart Stores comp-store sales increased 3.0 percent in August, as rival Target posted a 6.1 percent gain.