Year % 1995 36.06 1997 36.06 2001 36.1 2002 36.1 2003 36.08 2004 36.08 2005 36.08 2006 36.08 2007 36.15 2008 36.15 2009 36.15 2010 36.15 2011 36.15 2012 36.15 2013 35.89 2015 35.89 2016 35.89 2017 35.89