Year	years
1960	69.22586176916755
1961	69.65918521129902
1962	69.62488532074597
1963	69.78742164990382
1964	70.34134862618436
1965	70.42124856934727
1966	70.66853453307414
1967	70.85219716796941
1968	70.7676985090646
1969	70.68525408417904
1970	71.10592325445208
1971	71.25998760948428
1972	71.61254156913918
1973	71.72199110539339
1974	72.05551403824006
1975	72.12515586508984
1976	72.45130667467373
1977	72.89070312288865
1978	73.04259594289911
1979	73.38261383586503
1980	73.52957786259235
1981	73.80694558863345
1982	74.14825073509104
1983	74.21970000134252
1984	74.61630367191269
1985	74.75378186937294
1986	75.04654428805149
1987	75.36718961116377
1988	75.55261230051521
1989	75.73662837885699
1990	75.81149744953471
1991	75.9601490185218
1992	76.3008691097006
1993	76.4088353431057
1994	76.71942958175754
1995	76.87843960064238
1996	77.14462394659895
1997	77.5053252539498
1998	77.7161399032756
1999	77.94197902746048
2000	78.19590911247091
2001	78.54000408449431
2002	78.63019247806884
2003	78.65203406686571
2004	79.22825851141873
2005	79.37062691458564
2006	79.80319619142219
2007	80.0433364925514
2008	80.24671360961659
2009	80.4506879591034
2010	80.69361666630866
2011	81.17784684330226
2012	81.17414769787517
2013	81.45897312332843
2014	81.88967540804613
2015	81.51875355137686
2016	81.90869027981809
2017	81.88547750396376
2018	82.00454188892337
2019	82.281962811136
2020	81.49343123343594
2021	81.59494697171647
2022	81.70138410716419