Year	base year varies by country
1970	20.335984250831846
1971	21.596266889407477
1972	22.746234691582863
1973	24.300556135927977
1974	27.948536474589392
1975	31.331435974719906
1976	33.90448213382641
1977	36.271176026288074
1978	37.825437358324585
1979	39.457821981913064
1980	42.127362687897104
1981	44.97359008180858
1982	48.49756134638878
1983	50.949034151045666
1984	53.80922026083288
1985	55.895402705695275
1986	56.09909006514431
1987	56.88937950827392
1988	57.73387377716159
1989	60.28107524632232
1990	62.25335967284823
1991	63.93458328095173
1992	65.41658490664801
1993	67.42056828990582
1994	69.03622676881601
1995	69.88887392473954
1996	70.56279544295188
1997	71.3175258223486
1998	72.42255658968877
1999	73.33197837742455
2000	75.70793757727522
2001	77.12157892266627
2002	78.06714710433333
2003	79.79954687254501
2004	81.91558449095568
2005	84.1091328512385
2006	86.49848464854159
2007	88.15000687731775
2008	91.72122441071599
2009	90.22331246106765
2010	93.07822885349006
2011	95.89360126669041
2012	97.74575066211688
2013	98.68823493217334
2014	99.41735522800873
2015	100
2016	101.25497310703835
2017	103.5206937449847
2018	105.80225602668743
2019	107.0144774682575
2020	108.25607685654211
2021	112.78491976813898
2022	123.58058079625704
2023	127.05583272207906