Year	base year varies by country
1980	19.245076267235632
1981	21.049914224217616
1982	21.590734267675344
1983	18.461308623756224
1984	19.00702531463616
1985	17.37410232441853
1986	20.313770945786153
1987	19.854711130928145
1988	21.36973450636419
1989	24.279948031788003
1990	24.83645953919662
1991	25.453470694781384
1992	24.38419966706003
1993	24.154752893732738
1994	25.34977044041757
1995	23.865938470390578
1996	23.03575035852751
1997	23.203814415757332
1998	25.829059272202436
1999	28.81534718365356
2000	33.02812225378668
2001	36.633984148501554
2002	34.08125486717234
2003	32.36032401415093
2004	39.510745625047086
2005	39.347995912128624
2006	43.0830807543409
2007	51.37930150427129
2008	65.43030175533447
2009	84.16928307547198
2010	81.99443392241805
2011	80.88120376415746
2012	89.8583793619294
2013	94.394801419607
2014	100
2015	99.0272374943616
2016	96.78168531085558
2017	98.87542040835523
2018	102.38211010282066
2019	102.55968897021212
2020	107.66759504568032
2021	110.8397505269479
2022	112.54340184549221
2023	111.50216361619405