Year	years
1960	40.488
1961	40.979
1962	41.492
1963	41.981
1964	42.557
1965	43.134
1966	43.727
1967	44.363
1968	44.999
1969	45.659
1970	46.289
1971	46.913
1972	47.535
1973	48.116
1974	48.69
1975	49.223
1976	49.743
1977	50.239
1978	50.697
1979	51.139
1980	51.51
1981	51.82
1982	52.071
1983	52.244
1984	52.349
1985	52.418
1986	52.416
1987	52.353
1988	52.2
1989	51.959
1990	51.584
1991	51.21
1992	50.737
1993	50.284
1994	49.742
1995	49.201
1996	48.632
1997	48.042
1998	47.557
1999	47.113
2000	46.587
2001	46.434
2002	46.459
2003	46.605
2004	46.855
2005	47.287
2006	47.83
2007	48.425
2008	49.088
2009	49.82
2010	50.534
2011	51.167
2012	52.059
2013	52.727
2014	52.903
2015	54.512
2016	55.39
2017	56.051
2018	56.587
2019	57.106
2020	56.757
2021	56.303
2022	56.829