Year % 1993 14.83 1997 18.14 1998 18.55 2000 13.02 2003 8.91 2005 7.72 2006 6.91 2007 6.99 2008 7.64 2009 7.88 2010 7.96 2011 6.97 2012 8.94 2013 8.84 2014 8.74 2015 7.17 2016 7.52 2018 6.45 2019 6.64 2020 6.61 2021 6.38