Year % 1995 50.37 1998 44.38 1999 26.41 2000 26.06 2001 22.45 2002 19.01 2003 18.56 2004 15.9 2005 14.66 2006 14.63 2007 13.4 2008 12.19 2009 12.12 2010 13.01 2011 13.1 2012 13.34 2013 12.62 2014 12.75 2015 13.08 2016 13.4 2018 13.49 2019 12.74 2020 12.2 2021 12.81