Annual base year varies by country
1960 2.3638996660601435
1961 2.31564538634185
1962 2.326520069698422
1963 2.2718994283981253
1964 2.4114851958177983
1965 2.476695211067325
1966 2.384315308658881
1967 2.3980623572010655
1968 2.4907764061585387
1969 2.617316144691958
1970 2.30184725465757
1971 2.4437159454560717
1972 2.7724829687078714
1973 3.339473921605108
1974 3.768721726735643
1975 4.2184716737912185
1976 4.148111426551111
1977 4.501115671676519
1978 4.612798511606067
1979 5.313054995975827
1980 5.9899878756922345
1981 6.385272036619109
1982 6.631664486407171
1983 5.935239929970748
1984 4.950301836512579
1985 4.107925852360019
1986 4.437623179054845
1987 4.756659943144713
1988 5.126971470384563
1989 5.167624912395773
1990 5.120060488393984
1991 4.773058626704329
1992 4.09864175030439
1993 3.943257233332874
1994 3.789640843247407
1995 3.9047905300168426
1996 4.255611879404863
1997 4.133090764832232
1998 3.015145539827126
1999 3.256562613820694
2000 3.2770105711579114
2001 3.272721285085188
2002 3.361508586835165
2003 3.6573642221176206
2004 3.9357453892119247
2005 4.137908930428479
2006 4.054419223012251
2007 4.090701686400483
2008 4.1458943551676315
2009 8.101436590682459
2010 8.310092008181828
2011 8.490567348124687
2012 8.90286467276184
2013 9.623207939687973
2014 9.683350533964187
2015 9.718929066872679
2016 9.914677505442826
2017 10.217759784005104
2018 30.73191294045593
2019 100
2020 704.9458642280177
2021 1503.6141446739655
2022 5481.8855878659
2023 52653.44512090171