Year	years
1960	37.53950846791926
1961	43.20866719255628
1962	51.075175552090016
1963	51.577645430536855
1964	52.30769990862089
1965	52.225977630952926
1966	53.40658306667384
1967	54.282246568902565
1968	54.75909562924896
1969	55.46567248767453
1970	56.17837879428397
1971	57.034450530078914
1972	57.632912779972514
1973	58.59383329395396
1974	59.239780044558344
1975	60.00375039283239
1976	60.8415727209606
1977	61.597203439230285
1978	62.230442711510925
1979	62.84937108370171
1980	63.40211230010706
1981	63.90295230006353
1982	64.38581023663073
1983	64.80567016837475
1984	65.19891248857495
1985	65.57853430991746
1986	65.92460559329506
1987	66.27435621058639
1988	66.55337475523359
1989	66.87816388966148
1990	67.0961051258348
1991	67.31951383355506
1992	67.84115837197719
1993	68.30478723324137
1994	68.58938756856678
1995	69.02111828920937
1996	69.27885753293195
1997	69.67333845647573
1998	70.09906995923419
1999	70.31630115013948
2000	70.69246222059432
2001	71.28838264781953
2002	71.63867676709728
2003	71.97946960585405
2004	72.059917455124
2005	72.59736927036518
2006	72.95552388891244
2007	73.20366026524488
2008	73.1506565921811
2009	73.69942024940468
2010	73.91998870028215
2011	74.18704409463372
2012	74.43057924719311
2013	74.67384968039974
2014	74.92772481256013
2015	75.1521464652061
2016	75.35312048116512
2017	75.41573339439346
2018	75.83569328186586
2019	76.03665735077976
2020	75.96889032759968
2021	75.5711934120901
2022	76.21067445383898