Year	Years
1990	67.7
1991	67.5
1992	67.3
1993	67
1994	66.7
1995	66.5
1996	66.4
1997	66.5
1998	66.8
1999	67.1
2000	67.4
2001	67.7
2002	67.8
2003	68
2004	68.1
2005	68.1
2006	68.3
2007	68.5
2008	68.7
2009	68.9
2010	69.1
2011	69.3
2012	69.5
2013	69.7