US STOCKS-Nasdaq drops 3 pct, worst day since November 2011
* Nasdaq posts biggest daily percentage loss since Nov. 9, 2011
* Biotech index has worst day since August 2011
* VIX, Wall Street's fear index, jumps 15 percent
* Dow down 1.6 pct; S&P 500 off 2.1 pct; Nasdaq off 3.1 pct (Updates close with economic data, Gap shares down after the bell)
By Caroline Valetkevitch
NEW YORK, April 10 (Reuters) - The Nasdaq suffered its biggest drop in two-and-a-half years on Thursday after another sharp selloff in biotech and momentum names, including Gilead Sciences and TripAdvisor, increasing investor anxiety about a broader pullback.
The Nasdaq biotechnology index shed 5.6 percent, its biggest one-day drop since August 2011, adding to recent losses since a large drop in Gilead more than two weeks ago triggered a wider selloff for biotechs and other recent big gainers. That index is now down 18.8 percent since its Feb. 25 record close.
The S&P 500 also posted its biggest percentage loss since Feb. 3, while the Nasdaq has dropped 7 percent from its closing high for the year, set on March 5. All stocks in the Nasdaq 100 index posted a loss, with the exception of CH Robinson Worldwide, which ended up 1.6 percent at $53.80.
The selling also hit the shares of three companies in their first day of public trading after their initial public offerings were priced on Wednesday night. All three IPOs ended lower. Continuación...