Year % 2001 12.86 2002 12.94 2003 12.07 2004 12.07 2005 12.07 2006 11.9 2007 11.98 2008 11.98 2009 11.98 2010 11.98 2011 11.94 2012 11.94 2013 11.94 2014 11.29 2015 14.82 2016 13.02 2017 19.86 2018 16.83 2019 13.7 2020 13.7 2021 14.05