20 companies that lost the most

It wasn't so much bad luck as bad timing that made the $31 billion private-equity bet on this gambling giant go bad. TPG and Apollo Global Management bought Harrah's Entertainment, now called Caesars Entertainment, in 2007 just before the financial crisis hit. In the following years, faced with declining revenues and saddled with debt, the nation's largest casino operator struggled to turn a profit.

In 2010 Harrah's rebranded as Caesars and attempted to stage a public offering to raise some $500 million, but it withdrew those plans when it couldn't get the price it wanted. In February, the company gave the IPO another shot, this time only selling 1.4%, raising $16.3 million at $9 a share. At the time of the offering, it carried $22.5 billion in debt. On the upside, gambling in Las Vegas rose in 2011 for the second consecutive year, and Caesars says its online business is showing promise.

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