Year Percent 1995 15.05 1996 13.29 1997 14.15 1998 15.8 1999 17.28 2000 16.62 2001 16.6 2002 15.68 2003 15.54 2004 17.41 2005 16.5 2006 15.91 2007 15.5 2008 14.96 2009 11.91