Year % 1994 12.17 1999 14.66 2001 16.98 2002 16.26 2003 16.14 2004 15.97 2005 15.3 2006 15.24 2007 14.59 2008 10.77 2009 10.83 2010 8.64 2012 8.42 2013 8.07 2014 7.99 2015 7.26 2016 8.16 2017 8.21 2018 10.1 2019 7.39 2020 7.13 2021 5.81