Year Years 1990 69.6 1991 69.4 1992 68 1993 65.2 1994 63.6 1995 64.2 1996 65.9 1997 67.4 1998 67.6 1999 66.2 2000 65.4 2001 65.1 2002 64.9 2003 64.8 2004 65 2005 64.8 2006 66.1 2007 67.2 2008 67.6 2009 68.3 2010 68.7 2011 69.4 2012 70.4 2013 71.3