Year % 1993 25.98 1997 13.62 2001 13.66 2002 11.7 2003 13.28 2004 13.53 2005 13.18 2006 13.35 2007 13.08 2008 13.01 2009 12.72 2010 12.44 2011 12.46 2012 12.4 2013 11.76 2015 11.69 2016 13.59 2018 11.9 2020 12.76 2021 12.59