Year	years
1960	43.957
1961	44.55
1962	44.269
1963	45.619
1964	46.196
1965	46.744
1966	47.421
1967	48.034
1968	48.136
1969	49.438
1970	50.204
1971	51.124
1972	51.659
1973	52.946
1974	53.854
1975	54.761
1976	55.7
1977	56.577
1978	55.926
1979	58.55
1980	58.537
1981	56.715
1982	57.734
1983	58.748
1984	61.22
1985	61.893
1986	62.487
1987	62.823
1988	63.446
1989	65.718
1990	64.367
1991	66.459
1992	66.776
1993	67.139
1994	67.468
1995	67.785
1996	68.07
1997	68.359
1998	68.73
1999	69.297
2000	69.691
2001	69.955
2002	70.445
2003	69.823
2004	71.37
2005	71.838
2006	72.276
2007	72.772
2008	72.624
2009	72.698
2010	73.069
2011	73.679
2012	74.186
2013	74.449
2014	74.782
2015	75.124
2016	75.6
2017	75.971
2018	76.195
2019	76.103
2020	74.832
2021	73.875
2022	74.556