Year	Years
1990	72.7
1991	72.8
1992	72.9
1993	72.9
1994	72.8
1995	73.1
1996	73.6
1997	74.1
1998	74.3
1999	74
2000	74.3
2001	74.3
2002	74.3
2003	74.2
2004	74.6
2005	75
2006	74.8
2007	74.6
2008	74.4
2009	74.5
2010	74.7
2011	75
2012	75.2
2013	75.4