SAN FRANCISCO - Retailers are set to report another month of slowing sales after July offered little to draw in customers by the droves.Bargain-hunting shoppers delaying their purchases for the back-to-school season, as well as a timing shift in a tax-free sales week in certain states, may contribute to softer numbers for July, which is typically the first month for the introduction of fall merchandise. Analysts polled by Thomson Financial project that chain stores' same-store sales, or sales at stores open at least a year, collectively climbed 2.9% in July. That's below last year's 3.7% increase in the same period. Excluding Wal-Mart ( WMT), analysts peg the number to go up by 3.9%, compared with 4.7% on a comparable basis last year. Ken Perkins, president of research firm Retail Metrics, says that the back-to-school season is starting to follow the same patterns as the end-of-the-year holidays, when shoppers resist the temptation to buy the latest merchandise and instead wait for prices to come down. That's bad news for retailers for July -- but could mean a release of pent-up demand in August. As well, a shift in a tax-free sales week to August in states like Florida and Texas could also bode well for this month's results. Most major retailers plan to report their July results on Thursday. Apparel chains are expected to be the worst-performing group, with a projected same-store sales decline of 0.5%. That compares with an increase of 1.8% last July, according to Thomson.