Year	years
1960	45.825
1961	46.445
1962	47.166
1963	47.822
1964	48.588
1965	49.206
1966	49.434
1967	50.072
1968	50.626
1969	51.147
1970	51.638
1971	52.143
1972	52.627
1973	53.14
1974	53.516
1975	53.952
1976	54.333
1977	54.693
1978	55.041
1979	55.237
1980	51.834
1981	52.083
1982	52.564
1983	53.021
1984	53.682
1985	54.281
1986	54.868
1987	55.631
1988	55.741
1989	59.425
1990	59.393
1991	59.115
1992	58.734
1993	58.162
1994	57.203
1995	56.034
1996	54.5
1997	53.126
1998	51.864
1999	50.795
2000	49.908
2001	49.377
2002	49.37
2003	49.319
2004	49.285
2005	49.813
2006	50.382
2007	51.133
2008	51.885
2009	52.608
2010	53.275
2011	53.601
2012	54.433
2013	55.356
2014	56.544
2015	57.312
2016	58.113
2017	58.651
2018	58.931
2019	59.426
2020	59.058
2021	55.721
2022	54.592