Year % 1993 15.78 1995 15.24 1997 13.78 1998 13.76 1999 13.53 2000 13.93 2001 11.97 2002 11.77 2003 11.26 2004 9.69 2005 9.77 2006 2.52 2007 2.73 2008 1.34 2009 1.1 2010 1.38 2011 0.67 2013 0.44 2014 0.43 2015 0.62 2017 0.1 2018 0.08 2019 0.08 2020 0.07 2021 0.08