OPEC has kept up production to pressure high-cost rivals, such as the developing U.S. shale oil producers. The International Energy Agency expects it will take several years before OPEC can effectively price out high-cost producers.

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Friday’s “skew toward calls is just more of the same for USO options traders. At the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), the ETF’s 10-day call/put volume ratio of 1.65 ranks in the 89th annual percentile. In other words, calls have been bought to open over puts at a faster-than-usual clip,” adds Schaeffer’s.

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