NEW YORK (AP) -- Wal-Mart Stores Inc. Chief Financial Officer Tom Schoewe is retiring, the retailer announced Wednesday, and it has promoted Charles Holley to be his replacement.

Schoewe's retirement is the latest in a series of changes in the executive ranks at the world's largest retailer, which is trying to turn around sluggish U.S. sales fueled by a tough economy and merchandising problems.

Schoewe joined Wal-Mart 10 years ago and told the company's board last week he plans to retire.

Holley, 54, joined Wal-Mart in 1994 and is currently executive vice president of finance and treasurer. Before joining Wal-Mart, he worked for the Tandy Corp., now known as Radio Shack.

The transition will take place Nov. 30, and Schoewe will stay with the company through January to help with the transition.

The company said Holley's successor will be named later.

In a statement released Tuesday, CEO Mike Duke said, "Charles has great expectations both inside Wal-Mart and externally. He is a talented strategist who also thoroughly understands the details of our business and the financial markets." Duke also highlighted Holley's strong role in pioneering the company's international expansion.

Wal-Mart's international business generated revenue of $100 billion, accounting for 25 percent of total annual revenue in its latest fiscal year, and the sector is the fastest growing of all its units.

On Monday, Wal-Mart Stores Inc. announced it was offering to buy South African retailer Massmart Holdings Ltd. for about $4.25 billion in a bid to jump-start growth beyond its sluggish U.S. business.

Schoewe's departure is the latest change at the top. Eduardo Castro-Wright, Wal-Mart's president and CEO of the company's U.S. operations, resigned from his role for personal reasons in June. He was replaced by Bill Simon, who served as chief operating officer of Wal-Mart's U.S's business. Castro-Wright remains vice chairman.

John Fleming, Wal-Mart's chief merchandising officer, left the company Aug. 1 after 10 years. Fleming, who played a big role in shaping what was on store shelves, is being replaced by four executives who are splitting his duties.

Wal-Mart has struggled with five straight quarters of declines in revenue at stores open at least a year. That measure is considered a key indicator of a retailer's health. And its strategy remains in flux amid the management reshuffling and departures.

Wal-Mart had benefited early in the recession when more affluent shoppers were trading down to cheaper stores. But Wal-Mart's main blue collar customers are pulling back more amid a still stagnant job market. Wal-Mart also acknowledges that merchandising gaffes are partly to blame for weak sales. Last year, it cut back on too many products as part of its campaign to de-clutter its stores. It is now scrambling to fix the merchandising problems, and is going back to everyday low pricing. But its overall strategy is not clear.

"I think they are really trying to look at fresh approaches fro 2011," said Brian Sozzi, an analyst with Wall Street Strategies, who said he was surprised by Schoewe's retirement. "I think they're really trying to reset the table."

The retailer has more than 8,500 stores under 55 different names in 15 countries. It has more than 4,000 stores in the U.S. Its fiscal 2010 sales were $405 billion.