Norfolk Southern Corporation operates a major freight railroad network across the eastern United States, transporting coal, industrial goods, intermodal containers and other freight across an extensive rail network. Railroads benefit from significant barriers to entry, since building a competing rail network from scratch would require enormous capital investment and rights-of-way that are largely impractical to replicate, giving established railroads like Norfolk Southern durable competitive positions along their existing routes. The company's freight mix spans coal, which has declined as a share of its business as coal-fired power generation has decreased, alongside growing intermodal container traffic that benefits from international trade and e-commerce shipping volumes. Norfolk Southern's revenue and volumes track broader industrial production, international trade activity and coal-fired power generation demand, since rail freight volumes rise and fall with how much cargo needs to move across its eastern U.S. rail network.