Year % 1995 98.20247 1996 98.41565 1999 98.55891 2000 98.42178 2001 97.82749 2002 98.53069 2004 97.94154 2005 99.67278 2006 100 2007 99.69673 2008 98.86537 2009 99.76815 2011 98.58002 2012 99.95594 2013 99.66751 2014 99.57623 2015 99.81863 2016 99.5071 2017 99.68743