Year	base year varies by country
1960	5.03846182215888
1961	5.207927436053498
1962	5.383617566955072
1963	5.469945168200947
1964	5.649630837166007
1965	5.966394022344544
1966	6.2636121116115255
1967	6.437706815653643
1968	6.690792362524594
1969	7.0937143932415205
1970	7.749780182482893
1971	8.368648521319072
1972	8.97020805469244
1973	9.725040172864723
1974	11.189554633798956
1975	14.073184324248391
1976	16.20014451204693
1977	18.421264371358266
1978	20.531889388433896
1979	23.42001609363066
1980	28.034647977347266
1981	31.278050105584587
1982	33.5984982175373
1983	35.31968528932533
1984	37.09628223690994
1985	39.14091725852729
1986	40.83781535500543
1987	43.05961675687918
1988	45.70053768671528
1989	49.32726935914213
1990	53.21732539045579
1991	56.63339153013904
1992	58.514174737388245
1993	60.11339301066116
1994	60.951147434002216
1995	67.95382667327279
1996	70.76526439530019
1997	70.66117008457107
1998	71.56018152276454
1999	72.54280204757241
2000	73.37261035740804
2001	74.47712393032346
2002	76.05807829200214
2003	77.8779778415345
2004	79.91845592030357
2005	82.26432484592284
2006	84.55689472852603
2007	86.46155178659278
2008	89.40408055135536
2009	91.09481178880128
2010	92.53751796956394
2011	94.56333517399835
2012	96.01847920614152
2013	98.0512518387778
2014	99.3433498736803
2015	100
2016	101.96479827407785
2017	103.85781660719992
2018	105.85401825722234
2019	108.09360638120667
2020	113.58867828051842
2021	113.4518867458167
2022	119.29047831377486
2023	127.78333697736326