Year	current US$
1981	171918906625.679
1982	147411330929.252
1983	93600035914.0248
1984	61964094218.4885
1985	51743743944.3506
1986	46635563454.2591
1987	46490487165.4689
1988	41683676324.0034
1989	48224382056.9912
1990	55059616779.3787
1991	53212469567.1544
1992	47949820695.1903
1993	32371086018.7374
1994	37029892010.4317
1995	42798946852.2262
1996	42557619442.4268
1997	42844833913.1576
1998	41047940349.3425
1999	47381668283.6291
2000	63618908572.289
2001	49109899064.5057
2002	52694757393.117
2003	60533305048.3933
2004	80388867002.6342
2005	96677790263.1189
2006	145958380346.113
2007	112549297031.739
2008	149817493914.212
2009	114001987208.415
2010	138489815921.99
2011	163570520298.297
2012	208778732072.512
2013	159786629872.313
2014	187717409465.778
2015	136965546638.636
2016	119612190932.911
2017	125372899894.974