Year	current US$
1977	3089999.9532848583
1980	8520000.003278255
1981	7400000.017136337
1982	6949999.9675899735
1983	8249999.919906259
1984	8099999.89159405
1985	9719999.954104427
1986	8430000.096559523
1987	9319999.992847443
1988	12230000.041425232
1989	13450000.122189527
1990	18360000.0590086
1991	19560000.084340572
1992	14699999.973177915
1993	12919999.971985828
1994	21609999.999403957
1995	28919999.70376492
1996	27029999.986290913
1997	30250000.085681688
1998	29449999.868869793
1999	24640000.216662865
2000	19050000.1013279
2001	29689999.997615818
2002	39259999.99046326
2003	36570000.03755094
2004	37299999.74370003
2005	35970000.0435114
2006	40459999.978542335
2007	44010000.0500679
2008	63610000.5507469
2009	57559999.46594237
2010	59649999.49932098
2011	58049999.35626983
2012	59765779.07800675
2013	60320528.626441926
2014	57247568.01128387
2015	51037386.05976103
2016	44066483.25920105
2017	40923476.18937491
2018	40023610.32366753
2019	58567255.55658339
