Year Percent 1994 31.96109 1995 44.45305 1996 48.2616 1997 48.7144 1998 43.5866 1999 56.47029 2000 75.72713 2001 68.09555 2002 65.97625 2003 69.19507 2004 76.18319 2005 79.13007 2006 76.44942 2007 76.78692 2008 81.72935 2009 62.09806 2010 61.51917 2011 62.94134 2012 63.85005 2013 56.41864 2014 54.53785 2015 41.50125 2016 45.24647 2017 48.7098