Year	years
1960	40.33
1961	40.995
1962	41.403
1963	41.956
1964	42.275
1965	42.444
1966	40.15
1967	42.692
1968	42.844
1969	42.83
1970	42.815
1971	42.892
1972	41.55
1973	41.635
1974	39.453
1975	39.356
1976	41.895
1977	41.893
1978	41.9
1979	42.807
1980	43.217
1981	43.608
1982	43.767
1983	36.036
1984	36.429
1985	37.364
1986	37.811
1987	45.44
1988	45.061
1989	45.036
1990	44.557
1991	46.13
1992	46.901
1993	47.394
1994	47.861
1995	48.302
1996	48.924
1997	49.514
1998	49.927
1999	49.425
2000	50.538
2001	51.043
2002	51.517
2003	52.533
2004	53.235
2005	54.008
2006	55.149
2007	56.426
2008	57.592
2009	58.804
2010	59.73
2011	60.721
2012	61.543
2013	62.373
2014	62.905
2015	63.649
2016	64.392
2017	64.838
2018	65.412
2019	65.838
2020	65.371
2021	64.975
2022	65.645