Year % 1996 22.29 1999 21.91 2000 9.48 2001 9.38 2002 9.64 2003 9.63 2006 9.57 2007 9.56 2008 9.54 2009 9.53 2010 9.96 2011 9.94 2012 14.47 2013 14.46 2014 9.72 2015 9.73 2016 9.75 2017 12.31 2018 12.28 2019 12.25 2020 10.2