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

OSI Systems, Inc. (symbol: OSIS) was one of the worst losers of the trading
day today (2016-01-28), losing -31.78%. The number of shares that changed
hands was 3,515,597, or about 20 times the average daily volume in the
stock.
The closing price was $52.02, amounting to a market cap of $1,030,000,000,
about -46.23% off the highest price in the last 12 months. The stock has
been trading at a range between $48.19 and $96.75.
OSIS is in the Semiconductors industry, part of the Technology sector. It
first went public in 1997.
Looking at its valuation, the stock is now trading at 16.51 times earnings.