Year	base year varies by country
1970	18.306665904239676
1971	19.400666850213945
1972	20.996882250050135
1973	18.246512619121265
1974	20.743114680452013
1975	22.73831577146113
1976	24.641410845164348
1977	26.78189417303618
1978	27.86425927437735
1979	31.379575809765864
1980	35.35488655316998
1981	38.57590284704687
1982	41.42218382950211
1983	42.87633255252333
1984	44.63731626401384
1985	46.28254879187465
1986	47.41826725425189
1987	48.77450874073326
1988	50.78560420836434
1989	53.20148913297052
1990	55.85617797940483
1991	58.67375731681099
1992	60.442154297316684
1993	62.275807801194006
1994	63.910337246711926
1995	65.70438134270309
1996	67.54144485458767
1997	71.56102226078266
1998	73.47960034671691
1999	75.32549000441539
2000	74.48506850330496
2001	74.24808387007815
2002	77.23507037905081
2003	77.96599743773666
2004	79.50540207356421
2005	81.06633370833352
2006	83.88622689171815
2007	85.19133158636708
2008	89.85004391277786
2009	89.41814381276927
2010	90.27499572508648
2011	96.89782985335252
2012	102.89537094017564
2013	102.34745106377805
2014	103.33953961609137
2015	100
2016	107.34641600798582
2017	109.68173331494175
2018	106.97308312239555
2019	102.48424328964761
2020	109.46691425167477
2021	115.92256070289997
2022	117.15900748291726
2023	124.56140350877195