Year % 1995 22.36 1998 17.59 1999 19.98 2000 19.98 2001 20.1 2002 28.22 2003 17.66 2004 12.13 2005 11.56 2006 11.56 2007 9.83 2008 9.8 2009 9.16 2010 13.23 2011 12.34 2012 12.79 2013 12.6 2014 13.15 2015 13.07 2016 13.87 2017 12.8 2018 12.98 2019 16.43