Year	years
1960	68.121
1961	68.54
1962	68.002
1963	68.19
1964	68.675
1965	67.806
1966	67.715
1967	68.229
1968	67.567
1969	66.691
1970	66.656
1971	66.625
1972	66.927
1973	66.797
1974	66.825
1975	66.847
1976	67.011
1977	66.748
1978	66.904
1979	67.114
1980	66.75
1981	66.8
1982	66.85
1983	66.64
1984	66.79
1985	66.92
1986	67.47
1987	67.24
1988	67.12
1989	66.88
1990	66.64
1991	66.8
1992	67.6
1993	68.4
1994	68.3
1995	68.4
1996	68.8
1997	68.9
1998	68.6
1999	69
2000	69.1
2001	69.5
2002	69.8
2003	69.8
2004	70.3
2005	70.1
2006	70.4
2007	70.5
2008	70.9
2009	71.3
2010	71.6
2011	72.3
2012	72.5
2013	72.9
2014	73.3
2015	73.1
2016	73.8
2017	73.8
2018	73.9
2019	74.3
2020	73.5
2021	71.2
2022	73.7