Year	years
1960	72.736
1961	73.124
1962	73.04
1963	73.121
1964	74.2
1965	74.273
1966	74.405
1967	74.74
1968	74.497
1969	75.009
1970	74.714
1971	74.657
1972	74.721
1973	74.753
1974	74.816
1975	74.653
1976	74.52
1977	74.614
1978	74.335
1979	74.611
1980	74.308
1981	74.443
1982	74.806
1983	74.505
1984	74.553
1985	75.5
1986	75.98
1987	75.6
1988	75.9
1989	76.4
1990	75.6
1991	75.5
1992	75.4
1993	74.4
1994	74.3
1995	74.3
1996	74.3
1997	74.3
1998	74.4
1999	73.9
2000	74.7
2001	74.5
2002	74.1
2003	74.7
2004	75
2005	75.1
2006	75.5
2007	76.2
2008	76.5
2009	76.4
2010	76.5
2011	76.7
2012	77.6
2013	77.9
2014	78.4
2015	78.9
2016	79
2017	79.2
2018	79.4
2019	79.4
2020	77.866
2021	77.697
2022	78.384