Year % 1998 97.12019 1999 97.55176 2000 97.38769 2001 98.87515 2002 98.55883 2003 98.22453 2004 97.87571 2005 98.30874 2006 98.14936 2007 98.71911 2008 98.57096 2009 98.7782 2010 98.68454 2011 98.91449 2013 99.02707 2014 99.26875 2015 99.42044 2016 99.49038