Year % of total 1990 2.08266193037222 1995 0.407027364145973 2000 0.760649111460621 2005 0.857765650324815 2010 0.766856064755217 2011 0.954382243812235 2012 0.0957472118525149 2013 0.0982652845434529 2014 0 2015 0.104123111885068 2016 0 2017 0