Year	current US$
1990	474478379.662639
1991	476432633.869158
1992	450884683.925906
1993	420150631.750973
1994	442447375.048367
1995	463049896.04827
1996	411720165.809707
1997	336603126.626564
1998	312716554.350815
1999	292430742.71209
2000	252882298.485126
2001	248111192.678098
2002	251061570.251986
2003	297275340.284204
2004	299490379.9506
2005	282907874.433316
2006	284247503.554078
2007	308855452.278013
2008	345103638.270371
2009	356695266.407504
2010	353426237.019589
2011	416107463.926358
2012	386636054.626197
2013	383696218.055715
2014	373213214.063107
2015	333327440.380944
2016	297433679.567499
2017	273476202.598746
2018	282251804.640235
2019	276579096.517923
2020	294936668.613731
2021	314387941.213784