Year % 1995 4.08 1996 4.08 1997 4.08 1998 4.08 1999 4.08 2000 4.08 2001 4.08 2002 3.69 2003 3.58 2004 3.46 2005 3.37 2006 3.33 2007 3.3 2008 3.18 2009 3.14 2010 3.14 2011 3.14 2012 3.02 2013 2.99 2014 2.99 2015 4.2 2016 4.2 2017 4.23 2018 4.23 2019 4.23 2020 4.23 2021 4.23