The price of oil slipped again this week, closing at just over $37 per barrel. That sent oil stocks on a downward spiral, with several slumping by double digits. The worst performers, according to S&P Capital IQ data, were Oasis Petroleum (NYSE:OAS), Whiting Petroleum (NYSE:WLL), EP Energy (NYSE:EPE), Parker Drilling (OTC:PKD), and Carrizo Oil & Gas (NASDAQ:CRZO)

Oil ended 2015 much lower than anyone predicted. Worse yet, it is trading at a level that is below the breakeven point for many drillers. Oasis Petroleum and Whiting Petroleum, for example, both need a $50 oil price for cash flow breakeven. Meanwhile, only 55% of Carrizo Oil & Gas' drilling locations are even economic at a sub-$45 oil price, while $36 per barrel is the drilling breakeven point for two of EP Energy's key plays. Suffice it to say, these oil companies can't make much, if any, money at the current oil price. 

That means that oil and gas drilling activity could slow even further. Such a scenario would be bad news for a drilling contractor like Parker Drilling, which needs its customers to continue drilling to keep it in business. Needless to say, times are tough in the oil patch. 

To learn more about why these stocks moved so sharply this week, check out the following slideshow.

5 Oil Stocks That Were Crushed This Week (OAS, WLL, EPE, PKD, CRZO) from The Motley Fool.

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