Year	years
1960	66.0969756192829
1961	66.48837172349288
1962	66.40500608729799
1963	66.52994547649958
1964	66.94800468829253
1965	66.99241598816008
1966	67.16098712617705
1967	67.41551285489611
1968	67.1307172164788
1969	67.25450298815909
1970	67.53466653069313
1971	67.81660036327125
1972	67.99742029572782
1973	68.15981950230456
1974	68.5138097511943
1975	68.76481562985435
1976	69.0405600244022
1977	69.37676046912391
1978	69.50077290627686
1979	69.78797858604831
1980	69.86715470523667
1981	70.21242883991708
1982	70.55103646757934
1983	70.6670719127257
1984	70.91963026051985
1985	71.07223008389725
1986	71.43103294884988
1987	71.71862278666784
1988	71.82972110861236
1989	72.05030702199053
1990	72.12377464673023
1991	72.24687351592755
1992	72.32512026962478
1993	72.38263892455807
1994	72.69111489946513
1995	72.74432661653879
1996	73.20389984297775
1997	73.59885323403427
1998	73.85242183843263
1999	74.00474227500213
2000	74.31359880801656
2001	74.6426921208213
2002	74.82935262120321
2003	74.9692109240126
2004	75.41885425865037
2005	75.5244312497414
2006	75.87242759790536
2007	76.14382155005498
2008	76.33389209186899
2009	76.69739552424133
2010	76.95433283053903
2011	77.24051046574557
2012	77.42402111159589
2013	77.62714435070836
2014	77.89168535127953
2015	77.79471470055817
2016	77.94011846129543
2017	78.01808593818032
2018	78.10609778865272
2019	78.32880705124579
2020	77.30433568187826
2021	77.0295621043494
2022	77.59354951566637