Year	years
1960	57.78
1961	58.9
1962	59.75
1963	60.831
1964	61.851
1965	62.866
1966	63.846
1967	64.698
1968	65.645
1969	66.561
1970	67.371
1971	68.136
1972	68.913
1973	69.504
1974	70.074
1975	70.614
1976	70.948
1977	71.352
1978	71.578
1979	71.861
1980	72.986
1981	73.352
1982	73.79
1983	74.147
1984	74.41
1985	74.589
1986	74.9
1987	75.356
1988	75.796
1989	76.076
1990	76.433
1991	76.631
1992	76.972
1993	77.118
1994	77.258
1995	77.511
1996	77.746
1997	77.316
1998	78.021
1999	78.209
2000	78.419
2001	78.618
2002	78.823
2003	79.057
2004	79.237
2005	79.493
2006	79.686
2007	80.247
2008	80.429
2009	80.544
2010	80.688
2011	80.798
2012	80.703
2013	80.781
2014	81.013
2015	81.183
2016	81.377
2017	81.504
2018	81.608
2019	81.666
2020	79.676
2021	79.173
2022	79.472