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

Seadrill Limited Ordinary Share (symbol: SDRL) was one of the worst losers
of the trading day today (2016-05-31), losing -5.5%. The number of shares
that changed hands was 14,810,653, or about 1 times the average daily
volume in the stock.
The closing price was $3.09, amounting to a market cap of $1,550,000,000,
about -76.01% off the highest price in the last 12 months. The stock has
been trading at a range between $1.57 and $12.88.
SDRL is in the Oil & Gas Production industry, part of the Energy sector.