U.S. stocks retreated further on Thursday as declining telecom and natural resource shares overshadowed optimism about the economy spurred by a steep drop in the number of workers filing new claims for jobless benefits.

* The Dow Jones industrial average <.DJI> dropped 69.98 points, or 0.75 percent, to 9,210.99. The Standard & Poor's 500 Index <.SPX> lost 10.12 points, or 1.01 percent, to 992.60. The Nasdaq Composite Index <.IXIC> slid 24.50 points, or 1.23 percent, to 1,968.55.

(Reporting by Leah Schnurr; Editing by Jan Paschal)