Year Percent 1995 13.47 1996 13.91 1997 13.86 1998 14.13 1999 13.71 2000 14.34 2001 13.45 2002 11.24 2003 14.64 2004 14.84 2005 15.3 2006 15.78 2007 15.48 2008 11.81 2009 12.25 2010 13.3