Year	years
1960	42.903
1961	42.698
1962	44.46
1963	45.391
1964	46.28
1965	47.285
1966	48.305
1967	49.41
1968	50.468
1969	51.468
1970	52.89
1971	53.69
1972	54.86
1973	55.947
1974	56.927
1975	58.127
1976	59.007
1977	60.119
1978	60.611
1979	61.333
1980	62.055
1981	62.799
1982	63.441
1983	64.085
1984	64.817
1985	65.523
1986	66.205
1987	66.869
1988	67.608
1989	67.617
1990	67.924
1991	68.221
1992	68.461
1993	68.913
1994	69.312
1995	69.596
1996	69.967
1997	70.357
1998	70.535
1999	70.863
2000	71.115
2001	71.311
2002	71.525
2003	71.745
2004	71.859
2005	72.038
2006	72.189
2007	72.311
2008	72.451
2009	72.456
2010	72.552
2011	72.536
2012	72.669
2013	72.733
2014	72.757
2015	72.77
2016	72.76
2017	72.825
2018	72.864
2019	72.895
2020	71.837
2021	70.743
2022	71.367