Year	years
1960	46.612
1961	47.101
1962	47.451
1963	42.856
1964	47.626
1965	47.743
1966	47.631
1967	47.574
1968	47.238
1969	46.938
1970	46.704
1971	46.389
1972	46.069
1973	45.595
1974	44.992
1975	44.406
1976	44.118
1977	44.107
1978	44.61
1979	45.547
1980	46.748
1981	48.132
1982	49.372
1983	49.899
1984	50.134
1985	50.097
1986	49.933
1987	49.589
1988	49.355
1989	48.763
1990	46.517
1991	44.454
1992	42.12
1993	39.888
1994	13.071
1995	38.147
1996	39.2
1997	38.784
1998	39.662
1999	43.38
2000	45.902
2001	47.849
2002	50.124
2003	52.672
2004	54.666
2005	56.316
2006	57.491
2007	58.628
2008	59.582
2009	60.349
2010	60.738
2011	61.247
2012	61.946
2013	62.571
2014	62.764
2015	63.219
2016	63.33
2017	63.556
2018	64.013
2019	64.18
2020	64.358
2021	63.798
2022	64.813