Year Percent 1995 22.56 1996 23.66 1997 23.52 1998 20.44 1999 23.06 2000 26.27 2001 24.21 2002 29.96 2003 25.84 2004 25.37 2005 19.84 2006 19.22 2007 22.27 2008 23.74 2009 20.85 2010 21.59