Year	base year varies by country
1960	2.3924310175336703
1961	2.443758894021463
1962	2.5514215446823867
1963	2.7645577042975185
1964	3.0009737486836148
1965	3.250065655650762
1966	3.68137233177277
1967	3.9985669080334527
1968	4.095147636768629
1969	4.232063342450943
1970	4.2981784762169735
1971	4.527049648539665
1972	5.017763844171959
1973	5.912416869382599
1974	6.89786988136044
1975	6.784145973204636
1976	7.189964042814971
1977	7.595278805211393
1978	7.7821441068167925
1979	9.006123094380502
1980	10.042576632396738
1981	11.12994485012213
1982	12.03100994836291
1983	13.060005337978051
1984	14.094779970896976
1985	15.10872820088181
1986	16.134520261879892
1987	17.639531097340168
1988	19.091708205896154
1989	20.702439137073505
1990	22.911038248595933
1991	26.06172274601899
1992	28.39819589829321
1993	31.19876431245057
1994	34.312414958186864
1995	37.42204695182089
1996	40.2567738527222
1997	42.86391172770585
1998	46.29738286467632
1999	47.71796968773211
2000	49.4572754437583
2001	51.047631514634006
2002	52.9444000776795
2003	54.992182570183125
2004	58.14071226538506
2005	61.40932686552687
2006	66.56828647522327
2007	71.1910667115851
2008	77.73635176173852
2009	83.20927500210318
2010	91.96790896318461
2011	99.99999886086923
2012	107.93438624843215
2013	114.61175137195339
2014	118.4303363260216
2015	121.13006018974264
2016	125.0522211966558
2017	130.0158664075214
2018	135.06599505043292
2019	138.31503074018886
2020	144.97470295081357
2021	157.0872055922329
2022	167.68668534160304
2023	169.97806877718835