Year	current US$
1990	17518903.6038952
1991	24670969.1207048
1992	27524129.4031429
1993	25521810.3395262
1994	50782064.9823394
1995	48856672.3256307
1996	46059575.3415118
1997	42287763.4305765
1998	39905301.2508332
1999	38697437.5713936
2000	37878636.0169934
2001	38051468.6702151
2002	37196455.7841419
2003	36800101.1271599
2004	37878054.8841503
2005	39973242.2944619
2006	38745096.7292757
2007	40452617.0683134
2008	44732219.2156138
2009	43930137.4514628
2010	42471045.2218255
2011	44575038.6045412
2012	44687706.4032375
2013	43967890.8621475
2014	45758836.7428699
2015	45555687.4274455
2016	46681971.1949663
2017	45196673.0457342
2018	44081309.1127649
2019	44105095.3890783
2020	44164201.6739539
2021	44231015.3604416