Year	current US$
1990	21143677.576871
1991	21333993.5882457
1992	21576114.0548956
1993	20619584.6459349
1994	15270498.5940011
1995	17813693.2256314
1996	17316507.2387843
1997	14783031.1759459
1998	13884273.4395736
1999	13648696.3221991
2000	11157879.3821923
2001	11581063.2819081
2002	12516816.6003811
2003	15375143.3897207
2004	17183856.1707608
2005	17078064.5516306
2006	16865056.1316728
2007	19474042.5711116
2008	21160663.574534
2009	18668490.6393298
2010	16940834.2433929
2011	17998191.5666551
2012	16801561.5541102
2013	17141782.7029395
2014	18310370.8022328
2015	14815486.9693017
2016	14457316.9664299
2017	14298411.0112995
2018	14472975.0661171
2019	13846443.7549081
2020	13738929.8722059
2021	13718219.7084332