Year % 1988 5.18 1990 7.19 1991 7.26 1993 9.52 1996 7.59 1997 8.29 1999 8.24 2000 8.4 2001 8.01 2002 6.97 2003 7.38 2004 6.71 2005 6.96 2006 6.79 2007 6.73 2008 6.08 2009 5.41 2010 5.75 2011 5.67 2012 5.6 2013 4.5 2014 4.24 2015 4.38 2016 4.64 2017 4.38 2018 4.45 2019 14.63 2020 4.5 2021 4.89