STOCKS CRUSHED: Here's What You Need To Know

First, the scoreboard:

• Dow: 16,169.9 (-267.2, -1.6%)
• S&P 500: 1,833.1 (-39.0, -2.0%)
• Nasdaq: 4,054.1, (-129.7, -3.1%)

And now the top stories:

• It's hard to say if there was any one event that triggered today's sell-off. U.S. futures moved into the red a few hours before the U.S. markets opened.
• Today's underperformance of the Nasdaq continues a trend which started on March 5 in what strategist Ed Yardeni dubbed as the "internal correction." This correction is characterized as "money coming out of high-priced growth stocks and going into lower-priced value stocks," he explained. The big losers have been Internet software and services companies, health care technology companies, and biotechnology companies.
• The biggest losers in the S&P 500 today were indeed the biotech stocks including Alexion Pharmaceuticals, Gilead Sciences, Vertex Pharmaceuticals, Celgene, and Biogen Idec. The iShares Biotechnology Index (IBB) fell by over 5%. Industry analysts have generally been bullish on the industry based on the long-term profit potential of drugs in the developmental and regulatory pipeline. "Large cap biotech is now trading at a 2015 and 2016 PE discount to the S&P500!" exclaimed Credit Suisse's Ravi Mehrotra and Koon Ching in a recent note to clients.
• Big tech darlings also underperformed today. Netflix, Facebook, and Google were all losers.
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