Year % 1995 11.12 1997 9.42 1998 7.98 1999 7.24 2000 7.43 2001 7.3 2002 7.04 2003 7.13 2004 7.12 2005 6.86 2006 6.88 2007 7.02 2008 7.01 2009 7 2010 7 2011 7.01 2012 7.61 2013 7.53 2014 7.53 2015 7.53 2020 7.51 2021 7.51