Year	years
1960	75.87
1961	76.05
1962	76.05
1963	75.49
1964	76.08
1965	76.53
1966	76.71
1967	76.94
1968	76.8
1969	76.67
1970	77.32
1971	77.36
1972	77.51
1973	77.71
1974	77.96
1975	78.07
1976	78.21
1977	78.67
1978	78.63
1979	78.82
1980	79.17
1981	79.27
1982	79.54
1983	79.56
1984	79.61
1985	79.41
1986	79.76
1987	79.58
1988	79.56
1989	79.84
1990	79.8
1991	80.1
1992	80.36
1993	80.23
1994	80.64
1995	80.82
1996	81.07
1997	80.97
1998	81.3
1999	81.1
2000	81.4
2001	81.5
2002	81.6
2003	81.9
2004	82.3
2005	82.5
2006	82.7
2007	82.7
2008	83
2009	83.1
2010	83.2
2011	83.6
2012	83.5
2013	83.8
2014	84.2
2015	84.2
2016	84.2
2017	84.3
2018	84.5
2019	84.7
2020	84.9
2021	84.7
2022	84.2