EIA: “Diesel fuel consumption by Class I railroads represented 12% of all diesel fuel demand in the transportation sector in the United States in 2012. Diesel fuel consumption in 2012 was higher than the low of 3.2 billion gallons used during the 2009 economic recession, but still 14% below the 2006 peak of 4.2 billion gallons, and slightly below the 3.7 billion gallons consumed during 2011. Improvements in the energy efficiency of moving freight account for most of the reduction in railroad fuel use between 2006 and 2012. Class I railroads are large line-haul freight rail transportation from operators with annual revenues of $250 million or more. Class I railroads account for about 90% of all railroad freight revenue. The amount of energy needed to move freight by Class I railroads has decreased significantly over time. In 2012, it took 2.1 gallons of diesel fuel to move 1,000 revenue ton-miles of freight, compared to 2.4 gallons in 2006, 2.5 gallons in 2000, and 4.3 gallons of diesel fuel in 1980. Revenue ton-miles are the product of the weight of paid tonnage times the total number of miles it has been transported.”