Year	current US$
1990	19595654.8760582
1991	20871544.3021882
1992	22653953.993587
1993	26030072.7074527
1994	27896912.1344608
1995	31561923.4453925
1996	31018947.6066173
1997	32448691.7113169
1998	32675478.5480645
1999	30926286.6491486
2000	29771333.2855177
2001	27519880.0856166
2002	18348831.6730474
2003	14950570.3254393
2004	14397495.7261358
2005	15371517.1570869
2006	16892647.4529088
2007	19929302.6072203
2008	24012067.0950655
2009	24759763.1746469
2010	29475664.8989553
2011	35065768.2034478
2012	36114900.7808783
2013	39645502.628127
2014	38711773.0962477
2015	36692034.3706554
2016	37344965.3069151
2017	39978936.7632355
2018	40305231.7582748
2019	38508051.6699135
2020	36035968.5870622
2021	38318452.9691339