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

Penn West Petroleum Ltd (symbol: PWE) was one of the worst losers of the
trading day today (2015-07-22), losing -9.03%. The number of shares that
changed hands was 2,032,546, or about 1 times the average daily volume in
the stock.
The closing price was $1.31, amounting to a market cap of $657,830,000,
about -86.02% off the highest price in the last 12 months. The stock has
been trading at a range between $1.27 and $9.37.
PWE is in the Oil & Gas Production industry, part of the Energy sector.