Year	current US$
1987	4524736842.105263
1988	6146875000
1989	7429333333.333333
1990	4628430160.692213
1991	3629888888.888889
1992	3834402332.361517
1993	4162915193.4409432
1994	4278690154.286623
1995	4627661497.625651
1996	5178423153.692615
1997	5388858867.924528
1998	5455985520.745131
1999	6234435173.299102
2000	5118136861.236738
2001	4357045301.974583
2002	3671508263.6568146
2003	3793110548.314699
2004	4473018053.375196
2005	5299926321.275181
2006	6578528533.455846
2007	8870817108.304049
2008	12219896875.947832
2009	13935808736.234495
2010	19836378023.257214
2011	23626262112.21119
2012	26593441214.135277
2013	29641793851.117935
2014	31848809292.13436
2015	33751908600.33305
2016	33611118790.89296
2017	22859661703.849804
2018	18289272297.240097
2019	21175478668.01142
2020	22184600259.565918
2021	25647772259.910686
2022	31490341322.315315
2023	37309621605.17827