Total U.S. offshore oil production is 1.7 million barrels per day, almost all of it from the Gulf of Mexico, eerily close to the two million barrels per day of the historic correlation.

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On a day-to-day basis, the correlation can break, but over the long term it has been strong because the value of the Canadian dollar has good reason to be sensitive to the price of oil.

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You may not see it every day or every week, but that overall correlation will continue in our opinion, especially if you get closer to a mania.

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Constituents are ranked and chosen by their correlation to the spot price of oil in the quarter preceding the selection day.

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