Year Percent 1995 24.64 1996 21.55 1997 23.32 1998 21.15 1999 20.28 2000 18.99 2001 21.06 2002 17.44 2003 18.77 2004 12.21 2005 12.77 2006 9.479 2007 8.994 2008 8.911 2009 9.232 2010 7.769