9. Caterpillar
Jobs lost: 19,074
% drop (1 year): 17%
Remaining employees*: 93,813
Fortune 500 rank: 66
The machine builder pink-slipped skilled laborers repeatedly throughout 2009 as demand dropped for construction equipment. As recently as March 2010, more than 27,000 Caterpillar employees had been laid off since the housing market soured in 2008.
NEXT: General Electric
Last updated May 13 2010: 9:10 AM ET
* Full-time equivalent employees as of the end of 2009
