Year	base year varies by country
1970	0.09369269796628606
1971	0.10188060361410463
1972	0.12353958708674763
1973	0.1554746198066331
1974	0.21487782465300487
1975	0.3210268714897465
1976	0.42518901688079314
1977	0.5414161525176289
1978	0.7835591331585978
1979	1.1402473355043232
1980	1.7636367276439084
1981	2.6110857896014847
1982	3.9686588438774457
1983	7.323646042527784
1984	9.050191671761498
1985	12.169484328238212
1986	14.95035301694827
1987	17.548176819652817
1988	21.34204875749864
1989	26.862799804982117
1990	30.57227209722686
1991	32.43951218030542
1992	33.67631425785056
1993	34.646784739660106
1994	35.712980722377466
1995	36.45009637806959
1996	37.81513872773057
1997	38.614408072824425
1998	39.7785305343163
1999	41.1837693083061
2000	43.27072492548734
2001	47.07298314846275
2002	49.76372405444556
2003	50.681681280502865
2004	52.2762565476919
2005	53.1963983802234
2006	57.88930661132581
2007	61.04029416881988
2008	70.33299336019402
2009	79.94639657786837
2010	83.06615493244311
2011	86.59613777417839
2012	91.19720163087305
2013	94.49855813678018
2014	97.17518407334111
2015	100
2016	101.89008785361051
2017	102.35827289834522
2018	106.56399474777942
2019	111.6047129440835
2020	116.70380746036193
2021	122.42851409001472
2022	131.96565963049062
2023	143.5588353567325