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The Fortune 500's biggest losers

The mortgage meltdown and slumping auto sales hurt many Fortune 500 firms last year. In fact, 16 posted losses of at least $1 billion.

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1. General Motors
Fortune 500 rank: 4
2007 loss: $38.73 billion

Detroit's many woes hit GM hardest last year. The biggest of the Big Three took a tax loss to the tune of $39 billion in the third quarter, citing adverse factors like rising gasoline prices, more expensive raw materials and rival Toyota's new full-size trucks.

GM lost nearly $2 billion in its core auto business and $1.2 billion related to its stake in GMAC, which is No. 8 on the losers list. But there are signs of improvement: Losses in the auto business narrowed after an aggressive cost-cutting campaign that included 2,000 more layoffs. Total vehicle sales rose from 9.1 million in 2006 to 9.4 million last year thanks to increases outside North America--enough to tie Toyota and share the global No. 1 crown.
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Last updated April 24 2008: 11:01 AM ET