Year	years
1960	42.54316271091124
1961	42.74292036429336
1962	43.113427277931535
1963	43.15776604269421
1964	43.70505551426634
1965	43.68268944784816
1966	43.4901619048218
1967	44.11492829767045
1968	44.40326204973991
1969	44.57923180641826
1970	44.86645748041657
1971	45.28974204122899
1972	44.99770098235328
1973	45.8845481825658
1974	45.81069285972361
1975	46.00040219749875
1976	46.47991827045237
1977	46.70530816527544
1978	46.73887536856748
1979	47.285174311248234
1980	47.69243676670171
1981	48.03925277939169
1982	48.24697167739675
1983	46.650966669481406
1984	46.44017886855414
1985	46.79839272111957
1986	47.37359988465123
1987	47.69596348094974
1988	46.91936697724526
1989	48.37079758117695
1990	48.23369565941335
1991	48.10379934505298
1992	47.65126768708026
1993	47.909259823672606
1994	48.7719685025176
1995	48.839975733950055
1996	48.6764095511719
1997	48.909755023442194
1998	48.08776848457536
1999	49.107400519806724
2000	50.2368403625047
2001	50.573279213202945
2002	50.93839278174323
2003	51.50612464224342
2004	52.02917963495083
2005	52.679290782626566
2006	53.58226706898424
2007	54.29433482095784
2008	54.940962950368345
2009	55.75713389695766
2010	56.47964726343353
2011	57.2591451349442
2012	57.92971381249934
2013	58.47170389804509
2014	59.02814332571514
2015	59.51746409309895
2016	60.021248665923544
2017	60.535839282465304
2018	60.90518561802918
2019	61.29072100486868
2020	60.817484193584136
2021	59.894509127909345
2022	60.362146232912984