Year	base year varies by country
1960	5.521250149555322
1961	5.699145809146393
1962	5.694838852196073
1963	5.796786930705006
1964	5.987394662030997
1965	6.165809307333412
1966	6.331293186498158
1967	6.639487620424833
1968	6.7890488265769795
1969	7.111745138400341
1970	7.476762372466552
1971	7.864527226435346
1972	8.351268053451715
1973	9.101405218967168
1974	10.592221748430786
1975	12.338805895197641
1976	14.068668904879337
1977	15.674980773492187
1978	16.966210662140536
1979	18.431010398882506
1980	20.277197416921364
1981	22.208617394840758
1982	24.809019768834563
1983	27.32922122425423
1984	29.478037630069842
1985	30.85775908947368
1986	32.87847164456006
1987	35.18887632717263
1988	37.7153627250364
1989	41.19582264123083
1990	43.70554603988518
1991	45.025053608868824
1992	45.69150239591868
1993	46.0886661686587
1994	46.55876383708609
1995	47.62643896207431
1996	48.91778094462164
1997	49.5404295613078
1998	50.103013714471324
1999	50.34120394920599
2000	51.62528250117051
2001	54.01590387425952
2002	55.55012131573227
2003	57.20863670135052
2004	59.05777018368219
2005	61.3170305723149
2006	64.45363504999487
2007	67.66728036093424
2008	70.75955479441784
2009	74.26155891221596
2010	75.11694722675409
2011	79.77577436402673
2012	81.21585797241202
2013	81.08284141316496
2014	82.2219686561495
2015	81.70979054213423
2016	81.17396069834808
2017	84.1378109835792
2018	85.71860095611153
2019	88.68765562642835
2020	90.56235785446488
2021	93.3505683303578
2022	100
2023	106.55737568511417