Year	Years
1990	68.8
1991	68.9
1992	69
1993	69
1994	69
1995	69.1
1996	69.2
1997	69.3
1998	69.5
1999	69.8
2000	70.1
2001	70.4
2002	70.8
2003	71.1
2004	71.4
2005	71.8
2006	72.2
2007	72.5
2008	72.9
2009	73.1
2010	73.4
2011	73.7
2012	74
2013	74.2