Year % 1993 19.01 1997 22.16 1998 22.44 2000 16.17 2003 13.29 2005 11.92 2006 11.89 2007 11.89 2008 11.66 2009 11.63 2010 11.63 2011 11.55 2012 11.49 2013 11.49 2014 11.34 2015 11.44 2016 11.51 2018 11.63 2019 11.61 2020 11.6 2021 11.63