Year	years
1960	68.2
1961	68
1962	68
1963	67.9
1964	68.6
1965	68.6
1966	68.5
1967	69.1
1968	68.7
1969	68.6
1970	68.9
1971	69.2
1972	69.1
1973	69.3
1974	69.5
1975	69.7
1976	69.8
1977	70.2
1978	70.2
1979	70.3
1980	70.7
1981	71.1
1982	71.3
1983	71.5
1984	71.9
1985	71.8
1986	72.1
1987	72.5
1988	72.6
1989	72.9
1990	73.1
1991	73.4
1992	73.8
1993	73.8
1994	74.3
1995	74.3
1996	74.6
1997	74.65
1998	74.8
1999	75
2000	75.4
2001	75.7
2002	75.9
2003	76.3
2004	76.6
2005	77
2006	77.2
2007	77.4
2008	77.6
2009	78.1
2010	78.5
2011	79
2012	79.1
2013	79.2
2014	79.5
2015	79.2
2016	79.4
2017	79.5
2018	79.5
2019	79.6
2020	78.4
2021	78.7
2022	80.4