Year Percent 1995 73.57 1996 73.11 1997 69.78 1998 71.2 1999 69.43 2000 73.15 2001 72.67 2002 70.5 2003 70.82 2004 74.11 2005 74.71 2006 78.96 2007 80.46 2008 82.82 2009 78.24 2010 78.26