Year	base year varies by country
1967	10.000855680036128
1968	12.109680862756866
1969	12.54434043016516
1970	13.300732130105283
1971	14.19127468125998
1972	15.10977856860759
1973	15.707707677671761
1974	16.464512465468946
1975	20.24956199883831
1976	22.466147428228233
1977	24.277805521554637
1978	26.356507932188357
1979	29.36674929969626
1980	33.625413388373495
1981	37.25981866597342
1982	42.160863317847955
1983	46.72157266193801
1984	51.04425156001676
1985	49.266640436117456
1986	49.198504624548974
1987	48.26051918255646
1988	46.20803233373523
1989	47.7862115240644
1990	51.418973155970185
1991	48.42841621484579
1992	48.78621350145164
1993	50.36449344296084
1994	70.2898715757567
1995	81.40198605463983
1996	80.0571282168106
1997	84.52447434829979
1998	85.99484099726567
1999	100
2000	99.38027207961498
2001	104.02964104630807
2002	107.68407929303163
2003	99.50624419820568
2004	103.08709992623545
2005	110.8203953449931
2006	115.97007877470871
2007	121.25256929807774
2008	130.07535201531556
2009	136.10555709429488
2010	142.04656430085228
2011	159.35194116134866
2012	166.6907476143625
2013	167.77862444503194
2014	169.90713695783347
2015	174.80642518091085
2016	177.16827379731984
2017	180.59519225610424
2018	183.22820498448934
2019	186.7655025639116
2020	187.7597303792578
2021	194.0665309024437
2022	205.18234053437374
2023	211.04823235030895