$NRG is one of biggest losers #stocks today. read more:

NRG Energy, Inc. Common Stock (symbol: NRG) was one of the worst losers of
the trading day today (2015-12-02), losing -12.63%. The number of shares
that changed hands was 14,983,648, or about 2 times the average daily
volume in the stock.
The closing price was $10.79, amounting to a market cap of $3,390,000,000,
about -64.89% off the highest price in the last 12 months. The stock has
been trading at a range between $10.52 and $30.73.
NRG is in the Electric Utilities: Central industry, part of the Public
Utilities sector.