Year Percent 1995 42.59 1996 42.49 1997 36.88 1998 35.37 1999 34.51 2000 33.72 2001 33.07 2002 27.2 2003 26.85 2004 26.09 2005 27.23 2006 17.38 2007 14.5 2008 14.53 2009 15.15 2010 13.92