Year % 1994 16.65 1996 15.43 1998 14.64 2000 15.3 2002 14.45 2004 15.47 2006 14 2007 11.3 2008 11.79 2009 11.3 2010 11.13 2011 11.04 2012 11.69 2013 11.03 2014 12.22 2015 12.14 2016 10.19 2017 11.27 2018 10.82 2019 10.81 2020 11.18 2021 10.82