The number of Liberian-flagged vessels has doubled over the past decade to 3 500, after a record 586 new registrations were added last year. Within the total number of new vessel registrations in 2010, 149 were newbuildings. Net growth was 338 vessels, with a combined weight of 13.6-million gross tonnes, reported Tanker Operator. It said the average age of the 586 new registrations is 5.46- years, compared to an average age of 17.32- years for those vessels that have been removed from the Liberian Registry. This currently puts the average age of the Liberian-flagged fleet at 12- years. The report said the fleet growth comes after US-based Liberian International Ship & Corporate Registry (LISCR) took over the management of the Liberian Registry.