Year % 1989 84.97 1994 78.42 1998 23.26 1999 20.15 2000 20.15 2001 19.86 2002 19.94 2003 19.29 2004 18.3 2005 15.27 2006 15.27 2007 14.76 2008 15.6 2009 15.19 2010 15.16 2011 15.09 2012 15.87 2013 15.51 2015 15.56 2016 15.57 2019 15.81 2020 15.82 2021 15.89