Year	years
1960	67.5
1961	67.62
1962	66.86
1963	67.28
1964	67.44
1965	67.09
1966	67.18
1967	67.03
1968	66.47
1969	65.85
1970	66.05
1971	66.16
1972	66.84
1973	66.53
1974	66.75
1975	67
1976	67.04
1977	67.11
1978	67.2
1979	67.33
1980	66.8
1981	67.21
1982	67.32
1983	67.05
1984	67.34
1985	67.5
1986	67.49
1987	67.87
1988	68.1
1989	68.1
1990	67.54
1991	68.23
1992	68.54
1993	69.28
1994	69.48
1995	69.67
1996	70.3
1997	70.42
1998	71.1
1999	71.4
2000	71.7
2001	72.1
2002	72.1
2003	72
2004	72.6
2005	72.9
2006	73.5
2007	73.7
2008	74
2009	74.2
2010	74.4
2011	74.8
2012	75.1
2013	75.2
2014	75.8
2015	75.7
2016	76.1
2017	76.1
2018	76.2
2019	76.4
2020	75.2
2021	74.1
2022	76.2