Stocks traded calmly on the surface Monday, with relatively low volatility. The Dow was slightly higher, up 12 points at 16,817, and the S&P 500 was slightly lower, off 2 points at 1,961. But beneath the surface there was turbulence. Some momentum stocks were sharply lower, like Tesla, off more than 5.5 percent, GoPro, down nearly 10 percent, and Pandora down 3.5 percent. After the closing bell, Twitter joined the momentum losers, falling more than 10 percent on a disappointing forecast.
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"Energy and things related to energy just got killed again today. Just obliterated," said Steve Massocca of Wedbush Securities. The S&P energy sector fell 2 percent, the second-worst performer after the materials sector. The energy equipment sub-sector suffered an even worse 4.2 percent decline, as traders speculated weakening oil prices would result in less drilling.
Massocca said high dividend payers were also under fire, and selling hit MLPs. For instance, Holly Energy Partners was off more than 2 percent, and Teekay LNG Partners was off more than 2 percent.
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West Texas Intermediate fell below $80 to a more than two-year low, after Goldman Sachs said WTI could hit $75 in the first quarter of 2015. Even though WTI moved back to $81 a barrel in a short covering rally, the oil-related stocks remained under pressure.