Year	years
1960	39.97003949200387
1961	44.73787191896546
1962	51.17229807462837
1963	51.673324101342395
1964	52.33603444937853
1965	52.09476452996869
1966	53.32319863048315
1967	54.163859967702024
1968	54.56205173573487
1969	55.20654899768584
1970	55.817906410972256
1971	56.673100295787215
1972	57.19677872372917
1973	58.020337625109995
1974	58.552864992824105
1975	59.29974850520438
1976	60.07389177333919
1977	60.73445528590669
1978	61.27643167597803
1979	61.848598848373875
1980	62.324427344647475
1981	62.81170366350176
1982	63.263926283455504
1983	63.61227836432585
1984	64.01261820595829
1985	64.37480486223798
1986	64.68900164364507
1987	65.0277796600584
1988	65.25640913338846
1989	65.57213361941605
1990	65.81140441415691
1991	66.17356110787824
1992	66.59386831496207
1993	66.93996627220757
1994	67.28553596831416
1995	67.50568415512792
1996	67.82445460996546
1997	68.20255068813569
1998	68.50943174276271
1999	68.82537262281994
2000	69.16737192793941
2001	69.53476091293092
2002	69.8950323908049
2003	70.25598850783169
2004	70.40278577793049
2005	70.84341052573924
2006	71.19646728882822
2007	71.42445195574791
2008	71.44877343955152
2009	71.90066120810637
2010	72.1197221148044
2011	72.3531368765876
2012	72.58566762700163
2013	72.81940063159884
2014	73.07813560227594
2015	73.2890439440348
2016	73.44793024566991
2017	73.42091555988705
2018	73.86419508831652
2019	74.08658166285235
2020	73.98920133137999
2021	73.63887183193704
2022	74.22001342084026