Year	years
1960	54.42
1961	55.103
1962	55.776
1963	55.978
1964	56.441
1965	56.926
1966	57.141
1967	57.569
1968	57.995
1969	58.382
1970	58.581
1971	58.985
1972	59.283
1973	59.502
1974	59.71
1975	59.907
1976	60.095
1977	60.212
1978	60.502
1979	60.478
1980	60.915
1981	61.241
1982	61.473
1983	62.097
1984	62.495
1985	62.807
1986	62.992
1987	63.157
1988	63.669
1989	63.896
1990	64.305
1991	64.501
1992	64.584
1993	64.954
1994	65.016
1995	65.522
1996	65.835
1997	66.252
1998	66.522
1999	66.801
2000	66.921
2001	67.658
2002	66.956
2003	67.956
2004	68.06
2005	68.063
2006	68.394
2007	68.316
2008	68.205
2009	68.139
2010	68.214
2011	68.266
2012	68.307
2013	68.405
2014	68.37
2015	68.234
2016	68.395
2017	68.17
2018	67.92
2019	67.581
2020	67.106
2021	67.12
2022	67.325