Year	current US$
1976	821097140.372117
1977	729120661.681607
1978	890790731.809551
1979	1331884609.68257
1980	1417069328.95341
1981	1339918239.01216
1982	1062277417.37492
1983	1381350910.84227
1984	1240246678.33738
1985	1026886920.35853
1986	623032619.714622
1987	1064091608.59275
1988	1174046114.74548
1989	1233544902.94944
1990	1596105021.88751
1991	1551398729.52182
1992	702757016.316733
1993	306631391.692554
1994	565964179.803307
1995	526297593.291941
1996	1077411239.85696
1997	1146813146.4313
1998	1222090056.67541
1999	1580394620.3118
2000	1461593313.65593
2001	1620899996.41352
2002	1179283747.5364
2003	1469130240.43893
2004	1998590501.52284
2005	1779294172.80328
2006	2183443977.31811
2007	2307367391.56725
2008	3031766367.68927
2009	2717550748.1667
2010	3079201322.19075
2011	424311613.153103
2012	279018885.258331
2013	-458823711.411987
2014	1921329323.70792
2015	-85491401.6359158
2016	-551707192.679749
2017	-682982383.007304
2018	28743215.1111021
2019	57223186.0451918
2020	-2445253994.14234
2021	-1228339807.54552