Unless the context requires otherwise, references in this report to "Old Dominion," the "Company," "we," "us" and "our" refer to Old Dominion Freight Line, Inc.
We are a leading, less-than-truckload ("LTL"), union-free motor carrier providing regional, inter-regional and national LTL services through a single integrated organization. Our service offerings, which include expedited transportation, are provided through an expansive network of service centers located throughout the continental United States. Through strategic alliances, we also provide LTL services throughout North America. In addition to our core LTL services, we offer a range of value-added services including container drayage, truckload brokerage and supply chain consulting. More than 97% of our revenue has historically been derived from transporting LTL shipments for our customers, whose demand for our services is generally tied to industrial production and the overall health of the U.S. domestic economy.
We are the fourth largest LTL motor carrier in the United States, as measured by 2017 revenue, according to Transport Topics. We have increased our revenue and customer base over the past five years primarily through organic market share growth. Our infrastructure allows us to provide next-day and second-day service through each of our regions covering the continental United States. We opened 14 and 29 new service centers over the past five and ten years, respectively, for a total of 235 service centers at December 31, 2018. We believe this expansion produced increased capacity within our service center network and provides us with opportunities for future growth.