Year	years
1960	55.15387903525861
1961	55.69794806684
1962	56.145298719384584
1963	56.56533703728126
1964	57.073365881655114
1965	57.470838340229136
1966	57.88611811053562
1967	58.27295622921884
1968	58.64982599807495
1969	59.00128852410731
1970	59.07360052209529
1971	59.88494716529627
1972	60.251600215310695
1973	60.79768763637462
1974	61.217278517456826
1975	61.747581846198415
1976	61.98354163566171
1977	62.546730832095626
1978	62.9148417276927
1979	63.26144668172545
1980	63.686163178807185
1981	64.17350620024183
1982	64.50575734671888
1983	65.05341874678322
1984	65.46418389905767
1985	65.78107982716038
1986	66.37351820892671
1987	66.79348345626717
1988	67.20105898306657
1989	67.53892344243455
1990	67.82420170899216
1991	68.17744203276396
1992	68.50585022300622
1993	68.83139056966748
1994	69.20814176517261
1995	69.51853073201926
1996	69.89229490398796
1997	70.25264244017472
1998	70.50652955752716
1999	70.91135464686569
2000	71.22843627210625
2001	71.487118219397
2002	71.83684201994167
2003	72.02154933568345
2004	72.343865150839
2005	72.71463922322559
2006	72.92421268064516
2007	73.06568532329163
2008	73.28782721286656
2009	73.49195701668083
2010	73.38564295643201
2011	73.87154444023444
2012	74.09734270169334
2013	74.34648538783895
2014	74.55064770092821
2015	74.61196958205824
2016	74.57922973278502
2017	74.73349258442344
2018	74.85149792509877
2019	75.03834825865954
2020	73.0384695124212
2021	72.1484550673245
2022	73.75256852760107