<P> Today, railroads are primarily used to haul bulk quantities of cargo over long distances . Unless a manufacturing or distribution facility has a direct connection to the railroad, the remainder of the trip must be handled by truck . Recent implementation of "just in time" strategies have resulted in the increased use of trucks to help satisfy businesses' fluid inventory needs . Using this strategy, businesses gain the ability to reduce the costs associated with excess inventory and larger warehousing facilities by requiring more frequent deliveries . According to an industry group, many retail, commercial, and government services require daily or weekly deliveries to keep supplies or merchandise on hand . Many hospitals have also moved to "just in time" inventory systems . The nation's busiest gas stations require deliveries of fuel several times per day, while the average station receives fuel every two to three days . Grocery stores require deliveries of perishable food items every two to three days . </P> <P> Trucks are vitally important to U.S. industry, however, measuring the impact of trucking on the economy is more difficult, because trucking services are so intertwined with all sectors of the economy . According to the measurable share of the economy that trucking represents, the industry directly contributes about 5 percent to the gross domestic product annually . In addition, the industry plays a critical support role for other transportation modes and for other sectors of the economy such as the resource, manufacturing, construction, and wholesale and retail trade industries . </P> <P> Within the energy industry, approximately 4 percent of crude oil and petroleum products were shipped by truck in 2012 . These shipments are handled by oil and gas logistics firms, which are midstream service providers that also handle transport by pipeline, rail, and barge . Dominant companies in this space include Aux Sable, Bridger Group, DCP Midstream, Enbridge Energy Partners, Enterprise Products Partners, Genesis Energy, Gibson Energy, Inergy Midstream, Kinder Morgan Energy Partners, Oneok Partners, Sunoco Logistics, Targa Midstream Services, TransCanada, and Williams Companies . </P> <P> Agricultural products totaling $118,832,000, or 82.7 percent, were shipped by truck in 2007 (excluding animal feed, cereal grains, and forage products). About half of that agricultural freight was shipped by for - hire trucks and half by private trucks . More than 92 percent of prepared foods, including dairy products and prepared fruit, vegetable, and nut products, were moved by truck in 2007 . </P>

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