U.S. class I railroad locomotive fleet 1995-2020
Class I railroads
Class I railroads are the largest freight railroad operators in the U.S. Officially they are defined as having annual carrier operating revenues of 250 million U.S. dollars or more in 1991 dollars. Currently there are seven class I operators: Burlington Northern Santa Fe Railway, CSX Transportation, Grand Trunk Corporation, Kansas City Southern Railway, Norfolk Southern Combined Railroad Subsidiaries, Soo Line Corporation, and Union Pacific Railroad. Canadian National Railway and Canadian Pacific Railway are also considered as class I operators due to their significant U.S. presence. In total, around 118,799 miles of railroad was operated in the U.S. by class I operators in 2015. The largest two class I operators in terms of revenue are BNSF and Union Pacific. In 2021, Canadian Pacific Railway announced a merger with Kansas City Southern Railway, spanning the three main North American markets.
Freight in the U.S.
Over the last two decades, roughly 2.1 trillion ton-kilometers of rail freight were transported annually in the United States. Although a large number, this figure is a fraction of the 7.7 trillion ton-miles of total freight transported on average each year. Accordingly, even the largest class I rail operators generate significantly less revenue than the two main companies which provide road and air freight services, UPS and FedEx.