Year % 1995 10.23 1997 7.39 1998 10.08 1999 8.24 2000 7.5 2001 7.92 2002 7.02 2003 6.98 2004 6.53 2005 5.45 2006 5.25 2007 5.24 2008 4.99 2009 5.52 2010 5.32 2011 5.23 2012 9.49 2013 4.98 2014 5.62 2015 5.63 2020 8.76 2021 8.22