Year % 1991 57.57 1993 8.2 1996 8.27 1997 8.08 1998 7.71 1999 6.95 2000 6.87 2001 1.58 2002 1.53 2003 1.52 2004 1.55 2005 1.61 2006 1.32 2007 1.48 2008 2.63 2009 1.6 2010 1.37 2011 1.38 2012 1.3 2013 1.31 2014 1.43 2015 1.43 2016 1.33 2017 1.3 2018 1.31 2019 1.22 2020 1.24 2021 1.21