Year % 2001 11.37 2002 8.43 2003 8.4 2005 8.09 2006 7.31 2007 7.74 2008 7.07 2009 4.82 2010 4.77 2011 7.09 2012 4.77 2014 4.17 2016 3.55 2018 4.18 2020 4.14 2021 4.19