Year % 1995 42.36 1996 42.28 1997 42.28 1998 42.28 1999 42.28 2001 42.28 2002 42.28 2003 41.44 2004 41.44 2005 41.44 2006 41.44 2007 40.24 2008 40.24 2009 40.24 2010 40.24 2011 40.24 2012 40.24 2013 40.24 2014 40.24 2015 40.4 2016 40.4 2017 40.6 2018 40.6 2019 40.6 2020 40.6 2021 40.6