Year	current US$
1960	0.03164820464173545
1961	0.025611584094803568
1962	0.0052810403525530595
1963	-0.0219741813438865
1964	0.05568009024424249
1965	0.07189205176459654
1966	0.08869503114331367
1967	0.08819012760834134
1968	0.07602084610481356
1969	0.15040780526752726
1970	0.20519444681293458
1971	0.27477066001945
1972	0.3893431577129699
1973	0.5581891244992387
1974	1.617957044167286
1975	2.063208942825209
1976	4.7558229508363
1977	4.6451058806208625
1978	4.932175820033739
1979	4.900400791990566
1980	4.616118345869497
1981	2.779086570953865
1982	3.5422792210417753
1983	3.689685451571116
1984	3.5537093898065173
1985	4.1373356622029425
1986	4.081879773034279
1987	4.733264942573839
1988	5.8760147728668155
1989	5.399353137033463
1990	4.875464526389333
1991	3.4469524297398353
1992	2.299756933958444
1993	4.049466727302177
1994	4.328015342400011
1995	5.82334864122464
1996	5.219359611470869
1997	5.946466123999719
1998	7.264071001546246
1999	5.364904705384471
2000	4.058243099912847
2001	4.906129674783212
2002	5.560404389411615
2003	6.834406451408817
2004	8.861237952493992
2005	8.015213022884918
2006	7.30065716433918
2007	8.56707818381478
2008	11.130119181770867
2009	9.9750206215495
2010	11.731187337743327
2011	7.724775552191082
2012	7.583146434146662
2013	8.78411014472824
2014	23.079721891294813
2015	49.203283731986915
2016	237.88637390102213
2017	64.8106671121158
2018	66.18678316753021
2019	43.9297804517023
2020	46.82100037993786
2021	13.538997635870956
2022	12.262545785490454
