Year % 1995 77.27 1998 77.27 1999 77.43 2000 77.43 2001 77.43 2002 77.1 2003 77.1 2004 77.1 2005 77.1 2006 77.1 2007 77.1 2008 76.79 2009 76.79 2010 76.79 2011 76.79 2012 77.61 2013 77.61 2014 77.61 2015 77.61 2016 77.61 2018 77.83 2019 77.83 2020 77.83 2021 77.83