Ouch! 20 worst-performing stocks

Over the past decade, despite market ups and downs, Fortune 500 stocks paid off overall, returning nearly 7% per year to investors. Shareholders at these companies weren't so lucky.

1 of 20
1. Fannie Mae
Fortune 500 rank: 5
2010 revenue: $153.8 billion
10-year annualized return: -42.1%

A housing-industry giant that was built over the course of 70 years, Fannie Mae came crashing down in the summer of 2008. The company, along with its younger, smaller sister Freddie Mac, bought residential mortgages and sold guaranteed securities with the implicit backing of the U.S. government.

Before their implosion, Fannie and Freddie were involved in about half of the entire American mortgage industry. When the subprime mortgage market caved in, the duo took enormous write downs on their portfolios and shareholders were nearly wiped out. As losses mounted in the tens of billions, the government moved both entities into conservatorship.

NEXT: 2. Freddie Mac
Last updated May 05 2011: 2:52 PM ET
Top 50 Wal-Mart holds Exxon Mobil at bay and rules the Fortune 500 for the second year in a row. Which other companies made the top 50? More
They're hiring! These Fortune 100 employers have at least 350 openings each, totaling more than 96,000 jobs. What are they looking for in a new hire? More
20 most profitable Exxon Mobil rode high oil prices to a staggering $30 billion in profits. From Apple to Google, here are the other big winners. More