Year % 2000 39.96886823429202 2001 39.5444183282271 2002 39.2279696110547 2003 38.901736560333006 2004 38.52615593135557 2005 38.046885328652394 2006 37.54305215420585 2007 36.99555326431456 2008 36.43687569351108 2009 35.82630689250367 2010 35.27979160118671 2011 34.82251309507871 2012 34.40852971964502 2013 34.126959530120935 2014 33.87217785778669 2015 33.69083168051837 2016 33.630616168093894 2017 33.597549998511994 2018 33.52561821510982 2019 33.536651052659344