Year % 1995 11.06 1996 12.71 1997 11.87 1998 10.52 1999 10.01 2000 8.67 2001 8.43 2002 8.38 2003 8.85 2004 8.4 2005 8.4 2006 8.75 2007 8.57 2008 8.89 2009 7.98 2010 7.97 2011 7.79 2012 8.39 2013 8.38 2014 8.54 2016 8.55 2018 8.42 2019 8.42 2020 8.4 2021 8.42