Year % 1995 9.63 1996 8.29 1997 7.66 1998 5.24 1999 6.56 2000 6.9 2001 7 2002 5.56 2003 6.82 2004 5.82 2005 6.18 2006 4.97 2007 4.86 2008 3.7 2009 3.62 2010 4.66 2011 4.83 2012 4.01 2013 4.2 2014 3.93 2015 3.74 2017 3.56 2018 3.31 2019 3.21 2020 3.26 2021 3.12