Year % 1994 22.31 1996 19.09 1997 20.77 1998 14.72 2000 12.39 2001 11.55 2003 11.13 2006 20.67 2008 8.02 2009 9.63 2010 8.76 2011 8.59 2012 7.62 2013 7.44 2014 7.91 2015 7.9 2016 8.23 2019 9.01 2020 9.29 2021 10.04