Year % 1995 99.05708 2000 96.90948 2006 98.9542 2007 98.07733 2008 98.50327 2009 97.8637 2010 99.10345 2011 99.50483 2012 100 2013 99.78225 2014 99.05168 2015 98.28624 2016 97.95866 2017 98.57902