Year Percent 1996 97.34513 1997 38.08474 1998 48.88311 1999 50.81965 2000 32.06448 2001 27.85837 2002 22.74825 2003 27.62033 2004 31.30297 2005 38.6127 2006 55.52029 2007 68.86234 2008 29.86915 2009 51.2963 2010 78.82153 2011 73.64333 2012 91.69288 2013 79.94532 2014 92.00805 2015 81.5714 2016 78.63123 2017 92.60391