Year	base year varies by country
1960	4.8275402976243935
1961	4.781775248209535
1962	4.5601054953523565
1963	5.405308968521631
1964	5.114641063696944
1965	4.856595772504516
1966	5.033058560915749
1967	5.115970942534506
1968	5.5136375274649065
1969	5.766763728211882
1970	6.190276958650904
1971	6.611987127171029
1972	7.266131061882645
1973	8.920929513185023
1974	11.724009937083604
1975	15.166264662496143
1976	15.624434873712273
1977	17.14786973213144
1978	18.299778939563996
1979	20.564986597763536
1980	29.753032295776705
1981	33.38298823178907
1982	36.66979949874687
1983	38.746882793017456
1984	40.755227922371
1985	42.1875
1986	44.07475576950304
1987	47.308860060723156
1988	48.61333333333333
1989	51.930501930501926
1990	53.86663117263411
1991	56.28808864265928
1992	57.48274342781613
1993	60.4691825732187
1994	61.80545636337666
1995	62.43349201904228
1996	64.01831403178024
1997	64.60529699151452
1998	70.22806147744176
1999	73.34156886967264
2000	72.37137788290951
2001	74.00363416111448
2002	74.67548076923077
2003	75.50876367486178
2004	79.90952325716275
2005	85.23767016291006
2006	88.72932113925056
2007	96.37092193295862
2008	98.11228172975567
2009	96.31711697880411
2010	100.00031313684828
2011	103.61379835433542
2012	102.9890601316854
2013	105.95743588096728
2014	106.43454790372047
2015	104.50702073672365
2016	104.26180564795331
2017	106.98521007115343
2018	110.5464377170093
2019	115.25602386611801
2020	117.35873441260662
2021	122.8766540057355
2022	127.88486863633504
2023	133.9412761083153