Year % 2002 11.69 2004 11.75 2005 10.04 2006 10.04 2008 10.2 2009 10.19 2010 9.97 2011 9.97 2012 9.9 2013 9.9 2014 19.83 2015 19.83 2016 19.83 2018 17.13 2019 17.13 2020 17.28 2021 18.59