Year % 2002 21.15 2003 21.26 2005 20.2 2006 15.91 2007 13.66 2008 12.92 2009 10.26 2010 9.89 2011 9.8 2012 10.15 2013 9.4 2014 9.42 2015 10.04 2016 10.13 2018 10.09 2019 10.85 2020 11.1 2021 10.64