Year Percent 1995 13.98 1996 14.1 1997 15.17 1998 15.7 1999 15.37 2000 15.37 2001 15.15 2002 15.55 2003 16.41 2004 16.25 2005 15.4 2006 16.99 2007 16.12 2008 15.78 2009 14.52 2010 14.34