Year % 1993 17.16 1995 16.24 1997 13.83 1998 13.76 1999 13.76 2000 15.14 2001 12.34 2002 12.34 2003 12.32 2004 12.34 2005 11.95 2006 11.75 2007 11.75 2008 7.95 2009 4.9 2010 4.87 2011 2.94 2013 2.72 2014 2.72 2015 1.49 2017 1.51 2018 1.51 2019 1.51 2020 1.51 2021 1.51