Year % 1996 28.78 1997 29.07 1998 29.07 1999 29.07 2000 29.07 2001 29.07 2002 26.72 2003 26.72 2007 23.64 2010 23.64 2011 26.68 2012 26.68 2015 24.06 2016 24.06 2021 24.81