Year	current US$
1987	4258709.05564926
1988	4719781.25238282
1989	5601396.86841536
1990	5417386.23022145
1991	5348167.94078008
1992	4837412.46215514
1993	3944838.98707776
1994	3441037.61594382
1995	4283666.56863273
1996	4341287.55350818
1997	4110775.01152186
1998	3422441.99790925
1999	2473632.18512732
2000	2758605.83449308
2001	4017167.34940409
2002	3475164.0498114
2003	3329878.03087626
2004	6960564.40123258
2005	9221068.12336214
2006	10103375.3996526
2007	9781789.2969816
2008	26137612.9312917
2009	10803829.6609096
2010	16383743.8590124
2011	22202267.0742331
2012	12785691.8561103
2013	8874605.20732277
2014	6343064.2141941
2015	4166803.46662416
2016	4683673.24657368
2017	6164014.35145377
2018	8224862.89487497
2019	7589452.13455354
2020	5658924.22750122
2021	9980313.57710865