Year	years
1960	35.45
1961	36.823
1962	38.192
1963	39.417
1964	40.679
1965	41.885
1966	43.066
1967	44.285
1968	45.525
1969	46.684
1970	47.678
1971	48.934
1972	49.571
1973	50.859
1974	52.098
1975	53.297
1976	55.221
1977	56.257
1978	57.709
1979	59.151
1980	60.447
1981	61.646
1982	62.96
1983	64.217
1984	65.254
1985	66.272
1986	67.014
1987	67.887
1988	68.58
1989	69.156
1990	69.782
1991	70.189
1992	70.656
1993	71.165
1994	71.385
1995	71.99
1996	72.191
1997	72.415
1998	72.97
1999	73.184
2000	73.466
2001	73.808
2002	73.869
2003	74.14
2004	74.329
2005	74.396
2006	74.48
2007	74.461
2008	74.612
2009	74.681
2010	76.269
2011	76.608
2012	77.061
2013	77.246
2014	77.446
2015	77.687
2016	77.916
2017	77.924
2018	77.966
2019	78.002
2020	74.757
2021	72.541
2022	73.935