Year	Years
1990	70.2
1991	70.5
1992	70.7
1993	70.9
1994	71
1995	71.2
1996	71.3
1997	71.4
1998	71.5
1999	71.7
2000	72
2001	72.1
2002	72.3
2003	72.6
2004	73
2005	73.3
2006	73.6
2007	73.9
2008	74.2
2009	74.4
2010	74.3
2011	74.5
2012	74.5
2013	74.5