Jamaica's Usain Bolt has claimed his fourth consecutive world 200 metre title.In the final of the event at the World Championships in Beijing yesterday, he easily outstripped American rival Justin Gatlin.Bolt clocked a world-leading 19.55 seconds to beat Gatlin by nearly two-tenths, to add the 200 metres title to his 100 metre win at the championships. Bolt has now won 11 of the last 12 individual Olympic and world sprint titles dating back to 2008 Beijing Olympics.His only blip came after a false start in the 100 metres at the 2011 world championships in Daegu.