Year	years
1960	49.63
1961	50.15
1962	50.676
1963	51.228
1964	51.706
1965	52.294
1966	52.862
1967	53.444
1968	54.038
1969	54.591
1970	55.186
1971	55.766
1972	56.271
1973	56.95
1974	57.515
1975	58.087
1976	58.659
1977	59.223
1978	59.847
1979	60.446
1980	61.083
1981	61.824
1982	62.536
1983	63.239
1984	63.912
1985	64.231
1986	65.053
1987	64.578
1988	66.04
1989	66.134
1990	66.675
1991	67.203
1992	67.353
1993	67.528
1994	67.739
1995	67.885
1996	68.63
1997	68.708
1998	68.763
1999	68.237
2000	68.966
2001	69.037
2002	69.196
2003	69.276
2004	69.313
2005	69.39
2006	69.462
2007	69.544
2008	69.602
2009	69.653
2010	69.617
2011	69.551
2012	69.497
2013	69.534
2014	69.465
2015	69.513
2016	69.65
2017	69.71
2018	69.795
2019	69.877
2020	70.299
2021	70.449
2022	70.492