operate networks of passenger trains. By the early 1970s almost all passenger rail operation and ownership had been transferred to various federal, municipal and state agencies. Freight railroads continued to decline as motor freight captured a significant portion of the less-than-carload business. This loss of business, when combined with the highly regulated operating environment and constrained pricing power, forced many railroads into receivership and the nationalization of several critical eastern carriers into the Consolidated Rail Corporation (Conrail). Deregulation of the railroads by the Staggers Act in 1980 created a regulatory environment more favorable to the economics of the railroad industry. In the 1990s, the increase in foreign trade and intermodal container shipping led to a revival of the freight railroads, which have effectively consolidated into two eastern and two western private transportation networks: Union Pacific and BNSF in the west, and CSX and Norfolk Southern in the east. Canadian National Railway took over the Illinois Central route down the Mississippi River valley. In 2014, freight transportation establishments serving for-hire transportation and warehousing operations employed nearly 4.6 million workers and comprised 9.5 percent of the Nation's economic activity as measured by GDP. Truck driving is by far the largest freight transportation occupation, with approximately 2.83 million truck drivers. About 57.5 percent of these professional truck drivers operate heavy or Tractor-trailer trucks and 28.2 percent drive light or delivery service trucks. The Freight Facts and Figures 2015 indicates that the U.S. freight transportation system handled a record amount of freight in 2014. A daily average of approximately 55 million tons of freight valued at $49.3 billion moved across the transportation system in 2014 to meet the needs of the Nation's 122.5 million households, 7.5 million business establishments, and 90,056 Government units. Wartime expediency encouraged long distance pipeline transport of petroleum and natural gas, which was greatly expanded in the middle 20th century to take over most of the domestic long-haul market. Road transportation Infrastructure and private automobile use In comparison to some parts of the Western world, both the United States and Canada rely more heavily on motorized transit over walking and bicycling with 86% of American workers commuting to work via private vehicle, costing an estimated additional $1500 per year commuting compared to Western European counterparts. Car ownership is on the decline but still 91% nationally. Car ownership is universal, except in the largest cities where extensive mass transit and railroad