In the early years of the oil industry, prices moved sharply with the discovery of a new, large oil field or the sudden decline of an existing producer. Producers were like farmers, prey to things happening beyond their control and outside of their knowledge. Efforts to control the price (Standard Oil, Texas Railroad Commission, Achnacarry Agreement, and oil import quotas in the U.S.) enabled the industry, or at least the domestic part of it, to take prices as given. Most famously, when the Shultz Commission considered lifting oil import quotas in 1970, it assumed that prices would tend to decline, based on historical experience.
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