US STOCKS-Futures extend losses on recession worry

(Updates with futures extending losses)

NEW YORK Oct 23 (Reuters) - U.S. stock index futures extended losses on Thursday, putting Wall Street on track to slide at the open as investors reacted to disappointing earnings and outlooks.

Fears grew the global economy was headed for recession.

S&P 500 futures SPc1 dropped 17.20 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract.

Dow Jones industrial average futures DJc1 slid 158 points, and Nasdaq 100 NDc1 futures shed 18.50 points. (Reporting by Ellis Mnyandu; Editing by Kenneth Barry)