Year % 1995 10.5 1996 8.65 1997 6.75 1998 6.49 1999 6.46 2000 6.05 2001 7.92 2002 7.18 2003 5.26 2004 5.84 2005 6.12 2006 4.48 2007 5.12 2008 4.43 2009 3.64 2010 3 2011 2.77 2012 2.47 2013 2.67 2014 2.42 2016 2.59 2018 4.15 2019 3.81 2020 3.71 2021 3.71