Year	current US$
1990	23530190.4730011
1991	18186849.0140381
1992	15344205.4409383
1993	21356448.9668213
1994	20810256.6037637
1995	24470480.6960937
1996	27137465.9288287
1997	30465661.2670129
1998	31572245.7126329
1999	31039407.473762
2000	29944759.3636434
2001	28998682.3715454
2002	27937626.9153731
2003	24833731.8589462
2004	24290116.2402976
2005	24801152.9956049
2006	25998737.2281241
2007	30149217.9141997
2008	36028079.6033195
2009	34371263.4953907
2010	33799947.9093429
2011	38825217.8309982
2012	37767611.0900845
2013	36287931.7810663
2014	38816422.6230628
2015	39263192.8162113
2016	37043522.77787
2017	37790529.9477442
2018	37893088.5500275
2019	37210859.6996598
2020	35312788.5041088
2021	34913090.8340092