Year Percent 1995 37.38 1996 34.74 1997 34.31 1998 32.89 1999 32.43 2000 33.98 2001 33.88 2002 32.16 2003 32.03 2004 32.88 2005 32.93 2006 33.89 2007 34.26 2008 34.91 2009 32.16 2010 31.85