US STOCKS-Oil slump leads Wall St to worst week in 2-1/2 years
* Stocks drop after seven weeks of gains
* Oil volatility could spread to equities
* S&P closes near 50-day moving average
* Adobe up after results, to buy Fotolia
* Indexes off: Dow 1.8 percent, S&P 1.6 percent, Nasdaq 1.2 percent (Updates to close)
By Chuck Mikolajczak and Sinead Carew
NEW YORK, Dec 12 (Reuters) - U.S. stocks fell sharply on Friday, leaving the benchmark S&P 500 with its worst weekly performance since May 2012, as investors pulled back from the markets in response to oil's free-fall and more weak data out of China.
Oil's declines have underscored concerns about global demand, and with the S&P 500 having hit a record high only last week, investors were loath to fight the downward pressure on stocks, which accelerated in the final minutes of trading. The S&P dropped 3.5 percent on the week after seven straight weeks of gains.
The S&P energy sector was down 2.2 percent on the day. It is down 16.5 percent this year, the worst performing of 10 S&P sectors. Dow components Exxon Mobil and Chevron Corp both hit 52-week lows as U.S. crude oil fell below $58 a barrel, hitting five-year lows, on expectations of reduced worldwide energy demand. Continuación...