Year	years
1960	72
1961	72
1962	72
1963	71.9
1964	72.3
1965	71.9
1966	72.7
1967	72.9
1968	72.4
1969	72.1
1970	72.4
1971	72.65
1972	72.9
1973	73.4
1974	73.9
1975	74.2
1976	74.2
1977	74.5
1978	74.8
1979	74.9
1980	75.1
1981	75.2
1982	75.1
1983	75.1
1984	75
1985	75.5
1986	75.9
1987	76.1
1988	76.8
1989	76.7
1990	77.2
1991	77.4
1992	77.3
1993	77.3
1994	77.4
1995	77.8
1996	78.3
1997	78.6
1998	78.7
1999	78.8
2000	79.1
2001	79.6
2002	79.9
2003	80.7
2004	81.1
2005	81.3
2006	81.8
2007	82.3
2008	82.3
2009	82.3
2010	82.7
2011	83.3
2012	83.3
2013	83.6
2014	84.1
2015	83.9
2016	84.3
2017	84
2018	84.4
2019	84.5
2020	83.4
2021	83.8
2022	84.1