Year % of total 1990 99.99997955182091 1995 99.99877329576621 2000 99.9986083707764 2005 99.99872097215204 2010 99.99961355102627 2011 99.99961942836973 2012 99.9987167041697 2013 99.99838529827379 2014 99.94793501949574 2015 99.95292049885694 2016 99.32361677654488 2017 98.87351110927281