WageWorks Inc., which runs employee benefit programs, postponed indefinitely its $49 million initial public offering due to volatile market conditions, an underwriter said. Loyalty Alliance Enterprise Corp. was also sidelined because of the market, a different underwriter said. The Hong Kong-based marketing and data analytics company was on file to raise about $75 million.

Carbonite Inc., which sells Web-based computer backup products, cut the price range of its IPO by about a third to $10 to $11 per share from $15 to $17 per share.

So far this week, more than half of the 12 deals that were scheduled to price have run into problems.

The Standard & Poor's 500 is down nearly 18 percent since a peak at the start of May. Concerns about the U.S. economy and high levels of public debt in Europe have led to volatile trading over the last two weeks.