Year	current US$
1980	21228656.314015
1981	20879572.4222413
1982	29232754.0990338
1983	42033617.8652023
1984	38935765.0950036
1985	41823500.3320054
1986	38347336.0533693
1987	33561179.2670322
1988	50968972.7038137
1989	34097108.4110636
1990	60296369.2519767
1991	55004782.8762822
1992	80867066.106022
1993	106742636.032185
1994	117931223.944986
1995	413726.785543628
1996	5350630.26817681
1997	6861891.15988211
1998	9947063.50607653
1999	-4217274.66370541
2000	-8795047.02497831
2001	-36006236.1863726
2002	-43109093.0249198
2003	-28978128.9458097
2004	-41435121.6016744
2005	26878317.4572049
2006	47667216.6486911
2007	-11897573.3756499
2008	5708914.80790982
2009	159160907.046574
2010	144269464.990761
2011	128497259.115798
2012	163786728.660155
2013	182481172.34999
2014	74178677.2498303
2015	141437451.910218
2016	-32071627.9024671