Ocean container shipping is the ocean transportation of cargo in a standardized container. Global trade transported in containers increased from 100 million metric tons in 1980 to 1.7 billion metric tons in 2015. This growth is not only attributable to the technology used in container shipping, but also to government investments and international trading policies. Ocean container shipping has resulted in the creation of intermodal transportation and the technically advanced container port. By the mid-1980s, containerships from Asian ports might stop at a US West Coast Port and have its East Coast destined cargo loaded on a double-stack train for transport to the US East Coast as opposed to all-water service via the Panama Canal. Ocean container shipping has revolutionized the ocean transportation of general cargo. By the late 1990s, container shipping lines experienced financial difficulties. The lines responded by investing in larger containerships, undertaking mergers and acquisitions, and forming alliances.