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

GNC Holdings, Inc. Class A Comm (symbol: GNC) was one of the worst losers
of the trading day today (2016-12-23), losing -10.71%. The number of shares
that changed hands was 7,102,714, or about 3 times the average daily volume
in the stock.
The closing price was $10.84, amounting to a market cap of $741,450,000,
about -69.81% off the highest price in the last 12 months. The stock has
been trading at a range between $10.29 and $35.9.
GNC is in the Food Chains industry, part of the Consumer Non-Durables
sector. It first went public in 2011.
Looking at its valuation, the stock is now trading at 4.13 times earnings.