Year	base year varies by country
1965	5.923257554164758
1966	6.008032244554301
1967	6.198270365946874
1968	6.626560974370325
1969	6.827649222432737
1970	8.076384977895692
1971	8.729838149699463
1972	8.869694358086841
1973	9.550092655480828
1974	11.210734912376443
1975	12.093547445299532
1976	12.958070409101063
1977	14.233309192893154
1978	14.97015575193526
1979	15.95073905993623
1980	18.232986395509048
1981	20.105197074835473
1982	23.16703140832976
1983	26.156666918086618
1984	28.515231613252585
1985	30.364259477550625
1986	32.62771126546741
1987	34.307942529649424
1988	37.15191337164854
1989	40.032026539051884
1990	42.11095036186293
1991	45.337946325485284
1992	47.942733615727974
1993	50.64736830932514
1994	52.99718350867067
1995	55.72369633911091
1996	57.48981454483217
1997	66.41679661335249
1998	68.80554191442042
1999	71.22538516192941
2000	74.44901642048085
2001	73.18468473582679
2002	74.0755367009944
2003	76.6645354151304
2004	80.15319404990274
2005	81.47843897096975
2006	85.48204220295852
2007	88.03623419712429
2008	94.39377756589582
2009	95.90416782298125
2010	76.23433956206965
2011	81.0846627065486
2012	86.04019206893258
2013	92.01631689234468
2014	96.32986840083979
2015	100.00050410848415
2016	104.42217484008529
2017	111.23954350484252
2018	121.52022939669051
2019	130.4651877756108
2020	135.12585836238026
2021	143.59455313384072
2022	154.77269825681316
2023	166.7176362722191