Year	years
1960	41.687
1961	41.834
1962	42.05
1963	42.192
1964	42.471
1965	42.638
1966	42.924
1967	43.16
1968	43.636
1969	44.126
1970	44.512
1971	44.996
1972	45.507
1973	46.015
1974	46.321
1975	46.776
1976	47.304
1977	47.886
1978	48.346
1979	48.883
1980	49.084
1981	49.253
1982	49.34
1983	49.317
1984	49.243
1985	49.301
1986	49.456
1987	49.533
1988	49.752
1989	49.606
1990	49.549
1991	49.289
1992	48.977
1993	48.996
1994	48.857
1995	49.038
1996	49.141
1997	49.322
1998	49.773
1999	50.477
2000	51.203
2001	51.945
2002	52.632
2003	53.712
2004	54.433
2005	55.151
2006	55.635
2007	56.161
2008	56.739
2009	57.571
2010	58.35
2011	59.094
2012	59.931
2013	60.718
2014	61.589
2015	62.381
2016	63.172
2017	63.862
2018	64.475
2019	64.921
2020	64.373
2021	64.183
2022	64.72