Year % 2001 15.97 2002 15.99 2003 15.99 2005 14.35 2006 14.35 2007 14.35 2008 14.35 2010 12.1 2011 12.05 2012 12.05 2014 13.04 2016 13.06 2020 10.52 2021 11.74