Year	base year varies by country
1970	25.82857990858067
1971	27.656245482477367
1972	31.53211916277778
1973	32.661231400704295
1974	37.489436437971484
1975	37.48111917692425
1976	37.910058611532435
1977	37.40134841537282
1978	40.15788832889452
1979	44.17180182096191
1980	50.68952443752539
1981	55.04000404858542
1982	59.16982288527702
1983	60.989549218514014
1984	63.926486223689906
1985	66.02606166289468
1986	67.3125374925015
1987	69.17605216360403
1988	72.08092485549132
1989	75.48855388051368
1990	79.22497308934338
1991	83.26653306613227
1992	85.78998073217726
1993	88.37416481069043
1994	90.68517689207344
1995	92.72356884927518
1996	94.45713278002201
1997	95.07224064478935
1998	97.91608602464173
1999	97.14783878102554
2000	98.19597284698351
2001	99.28481578794486
2002	99.3783250961033
2003	99.01646341561813
2004	100
2005	102.0969946720524
2006	103.51074088378256
2007	106.79664788205201
2008	112.14179691878124
2009	118.15441349740684
2010	122.41149878843393
2011	124.36473636649097
2012	133.22261597741414
2013	134.07117030111812
2014	138.12534069376065
2015	130.87326473673787
2016	133.7448559670782
2017	146.53061224489795
2018	160
2019	154.50980392156865
2020	148.8
2021	151.75097276264592
2022	168.62745098039215
2023	178.98832684824905