Year % 1993 19.9 1997 18.61 1998 19.31 2000 13.14 2003 7.73 2005 10.16 2006 9.94 2007 8.3 2008 8.97 2009 11.31 2010 10.99 2011 8.81 2012 9.62 2013 8.35 2014 8.36 2015 7.87 2016 13.16 2018 22.94 2019 23.18 2020 28.63 2021 24.85