Year Percent 1994 26.78401 1995 25.792 1996 33.52092 1997 29.92625 1998 30.98629 1999 28.29447 2000 44.51342 2001 34.545 2002 38.0516 2003 41.98881 2004 40.17398 2005 43.40486 2006 44.51535 2007 43.56058 2008 38.72671 2009 38.35327 2010 35.37742 2011 33.11421 2012 33.18206 2013 32.33238 2014 31.70146 2015 33.10437 2016 33.82744 2017 34.08068