Year Percent 1995 61.27 1996 61.24 1997 55.4 1998 56.75 1999 57.85 2000 58.01 2001 57.48 2002 57.91 2003 59.69 2004 58.72 2005 62.64 2006 61.17 2007 63.33 2008 65.96 2009 64.71 2010 63.42