Dow Jones Industrial Average Down Triple Digits on GDP; Shake Shack Debuts

The Dow Jones Industrial Average (INDEXDJX:DJI) and S&P 500 Index (SPX) both stumbled out of the gate following weak gross domestic product (GDP) data, and appear resigned to ending January with a loss. Specifically, the advance GDP reading revealed a 2.6% economic expansion rate from October through December, below the consensus 3% forecast. At last check, the Dow was about 174 points, or 1%, lower, while the SPX was down 19.6 points, or 1% -- on track for its worst monthly performance in a year. Meanwhile, Wall Street newcomer Shake Shack Inc (NYSE:SHAK) is surging on its first day of trading, more than doubling in value around midday.

Continue reading for more on today's market -- and don't miss:

• 3 stocks to watch in February.
• Why Amazon.com, Inc.'s (NASDAQ:AMZN) earnings-induced rally could have legs.
• Plus ... Checking in on the CBOE Volatility Index (VIX), the SPDR S&P 500 ETF Trust (SPY), and other noteworthy stats at midday.

Among the stocks with notable call volume is drugmaker Intercept Pharmaceuticals Inc (NASDAQ:ICPT), with the contracts running at 11 times the expected intraday rate. The shares are surging on a "breakthrough therapy" designation from the FDA, up 17.1% to trade at $199.93. ICPT's most active option is the weekly 1/30 200-strike call, with traders opening positions to gamble on additional gains through the end of the session.

For more midday statistics and stocks on the move, head to page 2.

UGG designer Deckers Outdoor Corp (NYSE:DECK) is one of the biggest decliners on the Big Board today, following a poor showing in the earnings confessional and subsequent round of price-target cuts. The shares are currently 17.7% lower at $67.71, and earlier bottomed at an annual low of $67.30.

Biopharmaceutical firm Biogen Idec Inc (NASDAQ:BIIB) is one of the notable advancers on the Nasdaq, thanks to an encouraging fourth-quarter earnings report -- which was met with a bevy of bullish brokerage notes. At last check, the stock is up 10.2% to hover around $389.32, and earlier peaked at a record $397.

The CBOE Volatility Index (VIX) is up 2 points, or 10.6%, at 20.74.

Today's put/call volume ratio on the SPDR S&P 500 ETF Trust (SPY) is 1.49, with puts having a firm lead over calls. At last check, SPY is down 1.9 points, or 0.9%, at $200.12.