Year	base year varies by country
1970	5.197633529190696
1971	5.572464296943077
1972	6.026715829480974
1973	6.761109066807772
1974	8.076318584670036
1975	9.330922586707949
1976	10.832620369553508
1977	13.335237786934007
1978	15.843192441849022
1979	18.438733713864625
1980	21.424224476995853
1981	24.40838703140666
1982	27.714647033784352
1983	31.12169608775412
1984	34.20483561521247
1985	36.939909010870814
1986	40.190894742140365
1987	42.50670652027203
1988	44.92312406024609
1989	47.922416802903115
1990	51.053301323362255
1991	54.19935868267359
1992	57.52912015222974
1993	60.182618564606535
1994	62.71085713311094
1995	65.66731522995799
1996	67.65200394245343
1997	69.24961592411996
1998	70.54532916025676
1999	72.42803605890225
2000	75.72839012781881
2001	78.38194488479948
2002	80.86742843361056
2003	83.71633583608828
2004	86.98874816503732
2005	90.38799024235091
2006	93.96857281021995
2007	96.87413519301428
2008	99.35551772753738
2009	97.83734019056949
2010	98.62461048983633
2011	99.47637056534913
2012	99.52485189196861
2013	99.5244977539243
2014	99.61423440212803
2015	100
2016	100.24893357680168
2017	101.66893485755762
2018	103.14624712007947
2019	104.72280719383701
2020	105.25398123591762
2021	108.25793666053478
2022	115.53206034131567
2023	119.67158806432994