Year % 1997 83.6 2001 83.15 2002 81.32 2003 81.32 2005 81.32 2006 81.32 2007 81.32 2008 73.11 2009 73.11 2010 73.11 2011 73.11 2012 73.11 2014 73.11 2016 73.11 2018 69.4 2020 69.4 2021 69.4