Year % of total 1990 42.9506593310291 1995 39.1941665396791 2000 36.3957950944398 2005 7.45452968068004 2010 1.99807475576025 2011 0.38057954242825 2012 6.32397250238652 2013 0 2014 0.020412666169034 2015 33.9967589054326 2016 44.4347287480064 2017 45.0632690169155