Stock swings pinned on oil, technicals & triple witching

Cashin says: If Brent breaks $60, look out
Cashin says: If Brent breaks $60, look out   

It didn't take long for the U.S. stock market to erase Monday's opening rally and turn sharply lower, with strategists pointing to oil, technical factors and Friday's expiration of futures and options contracts as reasons for benchmark indexes jumping wildly throughout the session.

After jumping 122 points early on, the Dow Jones Industrial Average fell as much as 165 points, and was down nearly 50 points at 1 p.m. ET.

Trading in a 36-point range, the S&P 500 followed a similar route, rallying at the start and falling sharply as oil lost initial gains to turn sharply lower.

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"We broke the 50-day moving average on the first rollover," Art Hogan, chief market strategist at Wunderlich Securities, said of the 2,001 level on the S&P 500. "We then tested 1,987, which is the 100-day moving average, which if you look at a chart, looks pretty similar on the Dow. Now we're bouncing off the 100-day moving average," Hogan added.

"We also have quadruple witching, with that often comes more volatility as large firms unwind their stocks, versus options, versus futures positions. And we have pretty good volume today as large institutions are either closing positions out or rolling out to 2015," said JJ Kinahan, chief market strategist at TD Ameritrade.

After surging 78 percent last week, the Chicago Board Options Exchange Volatility Index, a measure of investor uncertainty known as the Vix, wavered between gains and losses on Monday.

Another large reason for the market's volatility is people took the opening rally as a chance to bank profits for the year, Kinahan said: "if you're having a good year, from a money management position, might be time to lighten up and put this in the bank."

"Like it or now, we're all oil traders now," Kinahan added of equities tracking crude's moves.

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