Year	constant 2015 US$
1970	966.6831133695263
1971	1042.5534087547578
1972	1057.2918777854898
1973	1161.9595660118175
1974	1082.3244800810687
1975	1114.8154140030108
1976	910.0873053978764
1977	775.3684266981588
1978	670.9901744422906
1979	652.1986529711019
1980	937.1775027591999
1981	1470.8545406846713
1982	2195.5082598429885
1983	1857.1228902507564
1984	1799.2967833013959
1985	1432.6333214602196
1986	1095.6160512016938
1987	914.2182805394509
1988	596.7564249681759
1989	441.72435098973216
1990	449.51710393462344
1991	679.5366585189558
1992	705.1566630447466
1993	493.1637739343813
1994	559.7746000983389
1995	48.81135480430997
1996	63.862709130407005
1997	213.59525943084924
1998	347.0960584403839
1999	272.61043500132473
2000	12.028780911770948
2001	184.38830092147657
2002	253.34287078298357
2003	484.46245171505086
2004	335.6659749026418
2005	458.2954084281177
2006	569.9323721763747
2007	601.4775449177769
2008	710.1940983916056
2009	859.0267646136031
2010	1139.1010211274831
2011	813.7569032849768
2012	1315.4640215560853
2013	1625.936495764027
2014	1792.8304480586721
2015	1473.5280938141977
2016	1149.5135842777247
2017	780.5380043795302
2018	862.4343852753889
2019	740.5549211422987
2020	590.5440286834303
2021	782.8247429427155