Year Percent 1995 37.78 1996 43.36 1997 42.02 1998 42.97 1999 44.25 2000 47.19 2001 42.28 2002 43.69 2003 42.64 2004 42.69 2005 40.3 2006 39.02 2007 36.23 2008 37.04 2009 36.24 2010 37.31