Year % 1996 9.8 1997 15.29 1998 9.8 1999 9.8 2000 19.83 2001 9.88 2002 10.49 2003 10.54 2004 10.5 2005 9.99 2006 9.24 2007 7.33 2008 8.65 2010 7.53 2011 8.64 2012 8.83 2013 8.71 2015 7.5 2016 7.14 2017 5.94 2018 5.96 2020 5.71 2021 5.26