The ETF purports to track the price of West Texas intermediate crude oil.

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The price spread between Brent crude oil, the European benchmark and West Texas Intermediate crude oil, the U.S. benchmark, widened sharply because of the loss of Libyan crude oil production.

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As you can see in the chart below, over the past 5-, 15- and 30-year cycles, West Texas Intermediate crude oil prices head higher in March, and have generally continued to climb through September.

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Cushing is the price settlement point for West Texas Intermediate Sweet Crude Oil on the New York Mercantile Exchange (NYMEX).

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The diversion of oil from the Midwest will narrow the gap between the West Texas Intermediate Oil and the Brent Crude.

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Indeed, Brent has gained in dominance in recent years as investors have moved away from West Texas Intermediate, the U.S. crude oil benchmark.

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Bakken crude even trades at a discount to West Texas Intermediate (WTI), the benchmark oil for the US set by prices in Cushing, Oklahoma.

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