Union Pacific operates one of the largest freight rail networks in the United States, moving industrial goods, agricultural products, coal, chemicals and intermodal containers across the western two-thirds of the country. Rail is a capital-intensive business with enormous fixed costs in track and equipment, which historically limited new competitors and left the market dominated by a small number of large railroads operating largely separate regional networks. Union Pacific's volumes and pricing power are closely tied to the broader industrial economy and to how much freight shifts between rail and trucking based on relative cost and fuel prices. The company has focused heavily on operating ratio, the share of revenue consumed by operating costs, as a key measure of efficiency that Wall Street watches closely.