ANALYSIS-Accounting irregularities may be on the rise in U.S.

*Recession taking its toll on balance sheets

*Experts see irregularities, restatements rising

*Investors often have little warning

By Emily Chasan

NEW YORK, Oct 28 (Reuters) - Corporate balance sheets may be showing signs of the wear and tear from the prolonged U.S. recession as accounting irregularities are starting to surface at growing numbers at U.S. companies.

"When things get difficult companies tend to stretch even further and utilize whatever games that they can get away with and sometimes they don't get away with them," David Tice, chief portfolio strategist for bear markets at Federated Investors, said in an interview with Reuters television on Wednesday.

Accounting irregularities are increasingly showing up in U.S. regulatory filings and corporate announcements.

Shares of Apollo Group Inc (APOL.O) sank 18 percent on Wednesday after the parent of University of Phoenix said the U.S. Securities and Exchange Commission had launched an informal inquiry into its revenue recognition practices.

Apollo is just one of several big name companies that have disclosed they have accounting issues over the last few weeks.

Internet retailer Overstock.com (OSTK.O) said last month that it was under scrutiny from government regulators over the way it accounted for some expenses. The company restated financial results in 2006 and 2008.

New York Sports Clubs owner Town Sports International Holdings Inc (CLUB.O) said last month that the SEC was formally investigating its deferral of certain payroll costs related to membership sales.

And jewelry chain Zale Corp (ZLC.N) said it will report fourth-quarter financial results on Thursday, after it twice-delayed its earnings results due to an accounting review of prepaid advertising costs.

"Statistically you can show any time you have a recession or some type of tremendous decline in an economy you're going to see financial pressures on companies," said Bruce Dorris, program director at the Association of Certified Fraud Examiners, noting that corporate employees can sometimes be motivated to be overly aggressive with accounting or commit outright fraud to meet targets, particularly in difficult economic times.

"If revenues start to dry up in other areas that they could use to mask it, it makes it much more difficult," Dorris said, adding that corporate frauds can unravel in a recession in the same way that Ponzi schemes like Bernard Madoff's become impossible to keep going. "The recession exacerbates the issue and makes it harder for them to control," Dorris added.

Nearly a third of corporate executives have expected that fraud and misconduct would rise in their organizations this year, according to a survey from accounting firm KPMG [KPMG.UL] in August. The most common causes of financial restatements are related to costs, expenses and revenue recognition problems, according to the Government Accountability Office.