#1 NII Holdings
Ticker: NIHD
YTD stock performance: -75%
Market cap: $1.1 billion
Fortune 500 rank: 369

Originally formed as the international unit of Nextel Communications, NII Holdings (NIHD, Fortune 500) is now an independent company that operates the Nextel brand in Latin America. It's located in Reston, Va., but does business in Brazil, Mexico, Argentina, Peru and Chile.

In recent years, Latin America's increasing savvy about mobile technology has put NII under intense competitive pressure. While its rivals cut prices and beefed up data plans, NII invested heavily in a "push-to-talk" capability. The focus on the antiquated technology hurt it, analysts say. This year it has hemorrhaged subscribers seeking mobile Internet access over walkie-talkie-style features. The company is now plowing money into 3G services, but it has faced delays in the rollout.

NII's woes began in earnest in 2012 when it announced its first quarter profit was down nearly 90% from the year before, a decline driven in part by unfavorable exchange rates. The bad news kept coming in the third quarter, when NII Holdings reported an $82 million net loss.

Source: CNNMoney
Data as of Dec. 7 market close, provided by S&P Capital IQ
  @FortuneMagazine - Last updated December 21 2012 02:35 PM ET
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