Year Percent 1994 53.8023 1995 49.45259 1996 53.78866 1997 56.18667 1998 56.13163 1999 52.04043 2000 55.03785 2001 58.45837 2002 54.29972 2003 59.59864 2004 62.5543 2005 59.45007 2006 60.92142 2007 63.54832 2008 69.42937 2009 70.22942 2010 66.75559 2011 84.0252 2012 75.36503 2013 70.41848 2014 60.70011 2015 63.41018 2016 74.26592 2017 93.63086