According to research by Automotive Fleet magazine, a listing of the top 10 most expensive cities in which to buy gasoline showed that while San Francisco and Los Angeles have been consistent in having the highest gasoline prices in the nation, that did not hold true for the entire West Coast. Prices in Seattle and Portland were 17 cents and 18 cents per gallon lower than those in Los Angeles, which itself has prices 10 cents per gallon lower than in San Francisco. The Midwest, where refiners are required to have ethanol mixed with gasoline to produce E85 fuel, has the second highest price group in the top 10 cities, but still roughly 10 cents per gallon lower than San Francisco and Los Angeles. Boston bottomed out the listing with prices slightly more than 30 cents per gallon lower than those in San Francisco.