Year	years
1960	65.41
1961	66.47
1962	66.29
1963	66.39
1964	66.8
1965	66.61
1966	66.88
1967	66.63
1968	66.76
1969	66.56
1970	66.5
1971	66.7
1972	67
1973	67.6
1974	67.5
1975	67.7
1976	68.2
1977	68.5
1978	68.5
1979	68.8
1980	69
1981	69.3
1982	69.4
1983	69.5
1984	70.1
1985	70.4
1986	71
1987	71.5
1988	71.9
1989	71.9
1990	72.3
1991	72.3
1992	72.5
1993	72.8
1994	73.2
1995	73.4
1996	73.7
1997	74.1
1998	74.5
1999	74.9
2000	75.2
2001	75.6
2002	75.8
2003	75.9
2004	76.4
2005	76.6
2006	77.1
2007	77.4
2008	77.7
2009	77.6
2010	77.8
2011	78.3
2012	78.4
2013	78.6
2014	79.1
2015	78.8
2016	79.3
2017	79.4
2018	79.4
2019	79.7
2020	78.9
2021	78.8
2022	78.8