Year	years
1960	37.75407013106873
1961	43.35870604862273
1962	51.127778588616174
1963	51.63096143187256
1964	52.359259125246986
1965	52.2876255150886
1966	53.4626550121212
1967	54.33756710844184
1968	54.81842520415731
1969	55.52560718480004
1970	56.23737502222755
1971	57.08999401255204
1972	57.68890518450411
1973	58.644670504466006
1974	59.28955690319152
1975	60.050774825698774
1976	60.8855814154324
1977	61.63789635931478
1978	62.26970746959086
1979	62.88678995404151
1980	63.43860951636265
1981	63.93939686983697
1982	64.422512918026
1983	64.84347721236858
1984	65.23824952654418
1985	65.61928450079448
1986	65.9668527286659
1987	66.31577954790575
1988	66.59575940800364
1989	66.91931059252455
1990	67.1365694989332
1991	67.3584271101554
1992	67.8799757949844
1993	68.35127148899417
1994	68.61720069885939
1995	68.91513566543142
1996	69.17060538632185
1997	69.56051513971013
1998	69.98020898326895
1999	70.19359489232777
2000	70.56483647750814
2001	71.15329235019573
2002	71.50019235688568
2003	71.94853627004508
2004	72.02660886408907
2005	72.55539597487237
2006	72.90653349271727
2007	73.14946089331208
2008	73.09787096488266
2009	73.64961213862406
2010	73.8761728997625
2011	74.14703458341131
2012	74.39577269644087
2013	74.64474646266214
2014	74.90326856954411
2015	75.12303517331867
2016	75.32186321906173
2017	75.38591131604952
2018	75.80143372483803
2019	76.00202030020539
2020	75.93602463703216
2021	75.54329129768432
2022	76.17851158278951