Year	base year varies by country
1975	15.762681783982666
1976	17.02822721614207
1977	18.54320913466668
1978	20.596506889868973
1979	23.302209236089777
1980	26.600250941376487
1981	29.89571674414238
1982	32.99070082629129
1983	34.65495107434882
1984	37.49039135526564
1985	39.615237500635246
1986	41.259534859032286
1987	42.85291567247347
1988	44.22150609429116
1989	46.322798823726245
1990	48.839574364437475
1991	50.7384600247615
1992	53.803764356003235
1993	56.388030710226055
1994	59.36023385239224
1995	67.431923792903
1996	69.21280840015217
1997	70.76103480309676
1998	72.15197010764605
1999	73.81290270122508
2000	75.83789029562443
2001	78.61378819272564
2002	78.84680353451918
2003	83.0948122571577
2004	85.34607357143817
2005	87.06963335641514
2006	89.75680253419071
2007	93.4711261379724
2008	97.89683451945126
2009	98.15441976239111
2010	100
2011	101.61624900011381
2012	103.32216146791305
2013	102.35327451574894
2014	100.98351904375369
2015	100.22186689114743
2016	99.64585915146333
2017	100.67916312811957
2018	101.69007459491404
2019	103.03506325550845
2020	101.6854649817741
2021	104.41653567282121
2022	110.75006023532185
2023	115.9835788411039