But Wal-Mart, the world's largest retailer, forecast profit for the current quarter that could miss Wall Street targets. It said it continued to see sales volatility from week to week.

Net income rose to $3.45 billion or 87 cents per share, in the second quarter ended July 31, from $2.95 billion, or 72 cents per share, a year earlier.

Earnings per share from continuing operations increased to 86 cents from 75 cents. Analysts on average had been expecting 84 cents, according to Reuters Estimates.

In the past year, Wal-Mart has benefited both from internal efforts to improve its business and from a weak US economy, which is driving shoppers to its stores in search of bargains.

The retailer also got a boost in the quarter from US tax rebate checks as shoppers came into its stores to spend the excess cash, but its sales waned later in the period as those funds dried up.

In July, Wal-Mart raised its second-quarter earnings-per-share forecast to a range of 82 cents to 84 cents from an earlier outlook of 78 cents to 81 cents, citing improved sales results.

Wal-Mart forecast third-quarter earnings per share from continuing operations at between 73 cents and 76 cents, while analysts on average expect 76 cents.