Year	years
1960	48.317
1961	48.73
1962	49.668
1963	50.25
1964	50.812
1965	51.465
1966	52.091
1967	52.632
1968	53.355
1969	53.896
1970	54.44
1971	54.966
1972	55.607
1973	54.415
1974	52.313
1975	57.548
1976	58.158
1977	58.746
1978	59.334
1979	59.908
1980	60.485
1981	61.016
1982	61.527
1983	62.137
1984	62.642
1985	62.996
1986	63.591
1987	64.032
1988	64.345
1989	64.856
1990	65.243
1991	65.752
1992	65.991
1993	66.251
1994	66.574
1995	67.139
1996	67.439
1997	67.777
1998	62.721
1999	68.422
2000	68.662
2001	69.006
2002	69.366
2003	69.507
2004	69.796
2005	70.104
2006	70.261
2007	70.376
2008	70.441
2009	70.911
2010	71.088
2011	71.439
2012	71.734
2013	71.963
2014	72.259
2015	72.487
2016	72.588
2017	72.692
2018	72.814
2019	72.881
2020	71.462
2021	70.123
2022	70.728