Year % 2001 9.82 2002 6.72 2003 7.22 2005 7.31 2006 6.66 2007 8.01 2008 6.1 2009 5.22 2010 5.15 2011 6.16 2012 5.15 2014 4.25 2016 3.7 2018 3.67 2020 3.67 2021 3.75