Year	current US$
1970	5.3473728138890575
1971	5.092133452067933
1972	5.6098431035176075
1973	14.53880477274174
1974	23.148425168282483
1975	34.36467693707154
1976	33.42202040246497
1977	38.01305774142603
1978	38.43400448439428
1979	39.95739358426102
1980	44.63857063747322
1981	41.05203135561431
1982	31.69282694060106
1983	25.03634427378249
1984	23.59505921580742
1985	24.519398223679357
1986	21.87590713343048
1987	23.6420841919752
1988	17.55898329353609
1989	16.88373573933329
1990	48.42179038133423
1991	44.01872209839476
1992	28.45266347217168
1993	21.727636025117835
1994	23.317258629545858
1995	18.82437805466559
1996	19.66092365319228
1997	17.846285620394713
1998	17.582134659518303
1999	15.722350081962583
2000	13.427720110935166
2001	13.368764430998779
2002	11.738829667636626
2003	23.09748381969391
2004	30.00259401669794
2005	84.43208313980274
2006	43.06701344426906
2007	45.09615024236094
2008	50.30530623689317
2009	24.018641694358976
2010	20.512202627366587
2011	23.268251616891764
2012	29.50882368884103
2013	47.573399647507024
2014	47.85754374520181
2015	43.70521997506367
2016	60.72732402119673
2017	64.61059124098158
2018	72.95762771002886
2019	60.60259569806241
2020	61.04558048920947
2021	76.36318863489511