reduce ethanol evaporative emissions and to avoid problems starting the engine during cold weather, the maximum blend of ethanol was set to 85%. There is also a seasonal reduction of the ethanol content to E70 (called winter E85 blend) in very cold regions, where temperatures fall below during the winter. In Wyoming for example, E70 is sold as E85 from October to May. E85 flex-fuel vehicles are becoming increasingly common in the Midwest, where corn is a major crop and is the primary feedstock for ethanol fuel production. Regional retail E85 prices vary widely across the US, with more favorable prices in the Midwest region, where most corn is grown and ethanol produced. Depending on the vehicle capabilities, the break-even price of E85 has to be between 25 and 30% lower than gasoline. Barriers to widespread adoption A 2005 survey found that 68% of American flex-fuel car owners were not aware they owned an E85 flex. This was because the exteriors of flex and non-flex vehicles look exactly the same; there is no sale price difference between them; the lack of consumers' awareness about E85s; and also the initial decision of American automakers of not putting any kind of exterior labeling, so buyers could be unaware they are purchasing an E85 vehicle. Since 2008, all new FFV models in the US feature a bright yellow gas cap to remind drivers of the E85 capabilities and proper flex-fuel badging. Some critics have argued that American automakers have been producing E85 flex models motivated by a loophole in the Corporate Average Fuel Economy (CAFE) requirements, that allows for a fuel economy credit for every flex-fuel vehicle sold, whether or not in practice these vehicles are fueled with E85. This loophole might allow the car industry to meet the CAFE targets in fuel economy just by spending between and that it cost to turn a conventional vehicle into a flex-fuel, without investing in new technology to improve fuel economy, and saving them the potential fines for not achieving that standard in a given model year. The CAFE standards proposed in 2011 for the period 2017–2025 will allow flexible-fuel vehicles to receive extra credit but only when the carmakers present data proving how much E85 such vehicles have actually consumed. A major restriction hampering sales of E85 flex vehicles, or fueling with E85, is the limited infrastructure available to sell E85 to the public