Year % 1998 16.77 1999 16.77 2000 16.77 2001 16.77 2002 16.77 2003 16.32 2004 16.32 2005 16.32 2006 16.32 2007 16.32 2008 16.1 2009 16.1 2010 16.1 2011 16.1 2012 17.2 2013 17.2 2015 17.2 2016 17.2 2019 17.32 2020 17.32 2021 17.32