Year	years
1960	66.507
1961	67.04
1962	67.148
1963	67.237
1964	67.658
1965	67.665
1966	67.725
1967	67.881
1968	67.537
1969	67.301
1970	67.495
1971	67.707
1972	67.855
1973	68.045
1974	68.396
1975	68.169
1976	68.621
1977	69.16
1978	69.107
1979	69.457
1980	69.613
1981	69.889
1982	70.179
1983	70.468
1984	70.944
1985	71.073
1986	71.31
1987	71.668
1988	71.868
1989	72.073
1990	71.911
1991	72.1
1992	72.6
1993	72.7
1994	73.1
1995	73.3
1996	73.6
1997	74
1998	74.5
1999	74.8
2000	75
2001	75.5
2002	75.4
2003	75.6
2004	75.9
2005	76.2
2006	76.4
2007	76.9
2008	77.2
2009	77.3
2010	77.5
2011	77.9
2012	78.1
2013	78.1
2014	78.7
2015	78.3
2016	78.6
2017	78.7
2018	78.6
2019	79
2020	78.7
2021	78.4
2022	78.33