Year Percent 1995 26.61 1996 26.53 1997 26.36 1998 26.7 1999 26.11 2000 24.5 2001 22.15 2002 22.39 2003 22.38 2004 21.19 2005 20.47 2006 19.88 2007 20.11 2008 19.65 2009 19.65 2010 19.6