Through its pricing terms and these options, MGRM had assumed a good deal of its customers’ oil price risk. To hedge this risk MGRM used a strategy known as the rolling stack. At the peril of some oversimplification, the strategy worked as follows. MGRM opened a long position in futures stacked in the near month contract. Each month MGRM would roll the stack over into the next near month contract, gradually decreasing the size of the position. Under this plan the total long position in the stack would always match the short position remaining due under the supply contracts. As of September 1993, the stack consisted of some 55 million barrels in futures on crude oil, heating oil, and gasoline, primarily in the near or next month contract, and a portfolio of similarly short-dated over-the-counter swap contracts bringing the total hedge to the full 154 million barrels of delivery obligated under the supply contracts. MGRM thus had a hedge ratio of one-to-one.