Price Difference between Regular and Premium Gasoline Has Grown Each Year Since 2011

Consumers have been paying less at the pump for both regular and premium gasoline since 2011, but the difference in price between unleaded premium and unleaded regular gasoline has been growing. In 2011, when the average price of regular gasoline was $3.72 per gallon (in 2015 constant dollars), the price of premium fuel was 7.5% (28 cents) higher. In 2015, when the average price of regular gasoline was $2.45 per gallon, the price of premium fuel was 17.1% (42 cents) higher.

The increasing difference between the regular and premium prices is being attributed to (1) the greater production of North American shale oil, from which it is easier to make low-octane, regular-grade fuel, and (2) the high price of high-octane blending components. Historically, the price difference between regular and premium fuel does not appear be linked to high or low gasoline prices.