Year	years
1960	66.606
1961	67.458
1962	66.563
1963	66.33
1964	67.26
1965	66.444
1966	67.195
1967	67.561
1968	67.618
1969	66.598
1970	66.568
1971	67.164
1972	68.4
1973	68.457
1974	70.079
1975	69.997
1976	70.043
1977	69.963
1978	70.022
1979	69.865
1980	69.719
1981	70.944
1982	69.542
1983	71.258
1984	71.218
1985	70.371
1986	71.672
1987	72.536
1988	72.813
1989	73.229
1990	73.499
1991	73.154
1992	73.222
1993	73.973
1994	74.734
1995	74.9
1996	75
1997	75.3
1998	75.1
1999	75.5
2000	76.3
2001	76.6
2002	76.3
2003	76.4
2004	77.4
2005	77.3
2006	77
2007	77.5
2008	77.1
2009	77.9
2010	79.3
2011	78.6
2012	78.6
2013	79.6
2014	79.9
2015	79.8
2016	80.6
2017	80.2
2018	80.4
2019	81.2
2020	80.3
2021	80.8
2022	80.7