Year	base year varies by country
1970	5.358980170672665
1971	6.740497362922364
1972	6.873359668609666
1973	8.060712486858854
1974	22.021464817384874
1975	22.95646777553553
1976	23.711989804783983
1977	26.019845079128395
1978	25.511540180599034
1979	35.92622661512117
1980	50.45313461341365
1981	56.15893174760244
1982	56.589512781234674
1983	51.34007718622063
1984	51.518579039071575
1985	54.02601029378935
1986	40.14065848698594
1987	44.46881932204547
1988	45.78924983630307
1989	45.00081977953148
1990	45.32366219633454
1991	45.30868427719842
1992	46.139648547259156
1993	42.73157995939014
1994	40.223032801753774
1995	42.174053403166056
1996	48.71534920521717
1997	46.418247625366085
1998	38.454680860705295
1999	45.4108855137532
2000	54.729975828614954
2001	50.50552728714517
2002	53.105698209343664
2003	55.71884385117376
2004	62.054782873621036
2005	75.56473696853232
2006	87.78836300374155
2007	91.56972577367685
2008	108.65933125630787
2009	90.00628646815592
2010	100
2011	117.22766291613551
2012	126.00437146795502
2013	126.28568130658957
2014	117.75133927172756
2015	87.18505631530323
2016	81.2234786004174
2017	94.40676110150983
2018	105.05392864553968
2019	104.5626326028559
2020	86.30539092262543
2021	110.23360634841382
2022	135.9618399633565
2023	123.43575349611267