Year Percent 1995 89.72272 1996 88.76871 1997 89.54675 1998 90.07576 1999 90.16769 2000 90.20541 2001 90.6515 2002 90.66011 2003 90.54499 2004 90.46044 2005 90.21025 2006 89.93519 2007 90.18926 2008 89.84731 2009 89.10545 2010 89.20834 2011 89.06312 2012 88.84919 2013 88.8692 2014 88.44594 2015 88.19289 2016 88.14513 2017 88.94146