By the early 1980s ships having a deadweight of about 400,000 tons and more made up about 5 % of the world tanker fleet.
Ekuqaleni kweminyaka yee1980 iinqanawa ezinobunzima bomthwalo wenqanawa omalunga namakhulu amane amawaka eetoni nangaphezulu zenza malunga neepesenti ezintlanu zelizwe zeenqanawa zokuthetha ipetroyile zomkhosi wenqanawa.