Year	Years
1990	66.1
1991	65.9
1992	65.1
1993	65.1
1994	65.1
1995	65.6
1996	66.1
1997	66.5
1998	67
1999	67.5
2000	68
2001	68.5
2002	68.9
2003	69.1
2004	69.3
2005	69.5
2006	69.9
2007	70.3
2008	70.6
2009	71
2010	71.4
2011	71.7
2012	72
2013	72.3