Year % 2001 13.87 2002 12.95 2003 12.94 2004 11.88 2005 11.97 2006 9.96 2007 10.87 2008 10.87 2009 10.87 2010 10.67 2011 10.26 2012 11.01 2013 11.48 2014 11.22 2015 9.58 2016 10.36 2017 16.07 2018 15.14 2019 11.69 2020 9.56 2021 9.64