Year Percent 2000 97.98621 2001 98.0473 2002 98.10839 2003 98.16948 2004 98.23056 2005 98.29165 2006 98.35274 2007 98.41383 2008 98.47491 2009 98.536 2010 98.59709 2011 98.65818 2012 98.71927 2013 98.78035 2014 98.78035 2015 98.78035