Year Percent 1995 14.27 1996 20.89 1997 21.11 1998 22.34 1999 21.04 2000 23.01 2001 23.15 2002 23.63 2003 34.42 2004 32.42 2005 26.22 2006 25.5 2007 24.95 2008 21.94 2009 28.17 2010 28.3