Year	years
1960	47.255
1961	47.817
1962	48.654
1963	49.5
1964	50.313
1965	50.949
1966	51.439
1967	51.72
1968	51.902
1969	51.994
1970	52.203
1971	52.454
1972	52.817
1973	53.247
1974	53.937
1975	54.753
1976	55.575
1977	56.296
1978	57.077
1979	57.853
1980	58.602
1981	58.921
1982	59.823
1983	60.815
1984	61.545
1985	62.371
1986	63.084
1987	63.916
1988	64.889
1989	65.326
1990	65.972
1991	66.504
1992	66.743
1993	67.137
1994	67.687
1995	68.304
1996	68.751
1997	69.242
1998	69.364
1999	69.62
2000	70.095
2001	70.431
2002	70.735
2003	70.659
2004	70.914
2005	71.226
2006	71.49
2007	71.706
2008	71.93
2009	72.087
2010	72.318
2011	72.605
2012	72.745
2013	72.82
2014	73.163
2015	73.081
2016	73.552
2017	73.974
2018	73.927
2019	73.711
2020	73.39
2021	72.608
2022	72.557