ExxonMobil the Exxon Building (1251 Avenue of the Americas), its former headquarters in Rockefeller Center, to a unit of Mitsui Real Estate Development Co. Ltd. in 1986 for $610 million, and in 1989, moved its headquarters from Manhattan, New York City to the Las Colinas area of Irving, Texas. John Walsh, president of Exxon subsidiary Friendswood Development Company, stated that Exxon left New York because the costs were too high. On March 24, 1989, the Exxon Valdez oil tanker struck Bligh Reef in Prince William Sound, Alaska and spilled more than of crude oil. The Exxon Valdez oil spill was the
Oil tanker has a capacity of over , a length overall of and a cargo capacity of . They were the first ULCCs to be double-hulled. To differentiate them from smaller ULCCs, these ships are sometimes given the "V-Plus" size designation. With the exception of the pipeline, the tanker is the most cost-effective way to move oil today. Worldwide, tankers carry some annually, and the cost of transportation by tanker amounts to only US$0.02 per gallon at the pump. In 1954 Shell Oil developed the average freight rate assessment (AFRA) system which classifies tankers of different sizes. To make it an independent