Year % 1995 4.09 1996 6.16 1997 6.09 1998 6.07 1999 6.08 2000 6.1 2001 6.32 2002 6.24 2003 6.24 2004 6.09 2005 6.27 2006 6.23 2007 6.16 2008 5.93 2009 5.9 2010 5.88 2011 5.83 2012 6.02 2013 5.92 2014 5.9 2015 4.39 2016 4.39 2017 4.39 2018 4.39 2019 4.39 2020 4.39 2021 4.39