Year % 1998 88.09717 1999 89.7153 2003 93.71267 2006 97.60241 2008 95.9914 2009 88.80615 2010 91.80819 2011 90.7775 2012 92.63052 2013 95.56447 2014 92.99217 2015 90.15751 2016 90.974 2017 91.57744