The Renewable Fuel Standard (RFS) mandates the amount of renewable fuels refineres must blend into the U.S. transportation fuel supply. As part of the RFS program, the U.S. Environmental Protection Agency (EPA) can grant annual waivers to some petroleum refineries, called small refinery exemptions (SREs), which are provided under conditions of economic hardship. Although these SREs lessen the number of tradable compliance credits that refineries use to comply with the RFS program, actual biofuel consumption is influenced by additional market factors.