Year	years
1960	47.842
1961	48.332
1962	48.809
1963	49.29
1964	49.733
1965	50.163
1966	50.56
1967	50.973
1968	51.403
1969	51.856
1970	52.322
1971	52.848
1972	53.397
1973	53.974
1974	54.556
1975	55.136
1976	55.739
1977	56.312
1978	56.815
1979	57.32
1980	57.807
1981	58.277
1982	58.71
1983	59.107
1984	59.337
1985	59.566
1986	59.533
1987	59.292
1988	58.469
1989	58.021
1990	57.057
1991	55.968
1992	54.865
1993	54.749
1994	52.848
1995	51.927
1996	51.669
1997	51.054
1998	50.342
1999	49.692
2000	49.136
2001	48.86
2002	48.837
2003	49.199
2004	49.902
2005	50.783
2006	52.596
2007	54.371
2008	55.689
2009	56.431
2010	58.093
2011	58.173
2012	58.587
2013	59.302
2014	59.781
2015	61.262
2016	62.77
2017	63.968
2018	63.336
2019	62.934
2020	63.142
2021	58.691
2022	63.328