Year % 1995 6.98 1997 8.68 2002 7.5 2006 5.09 2007 5.04 2008 5.05 2009 4.47 2010 4.54 2011 4.38 2012 4.38 2013 4.46 2014 4.48 2015 4.48 2016 4.48 2017 4.48 2018 4.48 2019 6.48 2020 4.48 2021 4.53