Year	Years
1990	69.8
1991	70.3
1992	70.1
1993	69.8
1994	69.4
1995	69.3
1996	69
1997	69.1
1998	69.8
1999	70.5
2000	70.8
2001	70.9
2002	71.2
2003	71.6
2004	72
2005	72.6
2006	73
2007	73.3
2008	73.4
2009	73.5
2010	74
2011	74.9
2012	75.6
2013	76