Year	years
1960	37.881
1961	37.941
1962	36.548
1963	42.339
1964	42.224
1965	42.164
1966	42.062
1967	42.108
1968	42.221
1969	42.343
1970	42.712
1971	43.205
1972	43.834
1973	44.583
1974	45.372
1975	46.294
1976	47.236
1977	48.302
1978	49.38
1979	50.657
1980	51.983
1981	53.846
1982	55.806
1983	57.835
1984	60.102
1985	62.027
1986	63.462
1987	64.439
1988	66.034
1989	66.064
1990	66.313
1991	66.378
1992	66.238
1993	66.263
1994	65.621
1995	65.489
1996	67.134
1997	67.49
1998	67.744
1999	68.703
2000	69.068
2001	69.498
2002	69.943
2003	70.344
2004	70.735
2005	71.069
2006	71.313
2007	71.499
2008	71.841
2009	72.413
2010	72.769
2011	73.04
2012	72.971
2013	73.43
2014	73.803
2015	74.456
2016	74.693
2017	74.7
2018	74.966
2019	75.238
2020	73.082
2021	74.879
2022	75.853