Year % 1993 22.54 1998 23.23 1999 14.87 2000 14.12 2002 14.71 2003 14.95 2004 14.86 2005 14.8 2006 12.74 2007 12.69 2008 13.78 2009 12.18 2010 12.29 2011 12.38 2012 12.13 2013 11.21 2014 12.12 2015 12.07 2016 11.89 2018 11.11 2019 12.57 2020 11.17 2021 12.26