Year	current US$
1981	1636707.89715661
1982	1842381.10685378
1983	2217363.52325363
1984	2407106.67490394
1985	2606627.0623389
1986	3365341.92049263
1987	3868011.80443251
1988	4240953.19859834
1989	4353466.28883878
1990	5063128.30100615
1991	4520789.02614761
1992	5441118.2288682
1993	7866000.90730723
1994	8206360.8137998
1995	11984494.7073883
1996	10795133.8427411
1997	11075144.4723499
1998	11600516.1443597
1999	11805142.4203248
2000	12207261.6511327
2001	12406075.6330288
2002	13725344.706392
2003	13816174.6113623
2004	13482464.9474101
2005	13182513.7358814
2006	13790012.2029823
2007	15377919.4187019
2008	14188308.1509426
2009	14614696.2094263
2010	16492835.3143836
2011	17747494.9117826
2012	17867812.5242379
2013	19502755.4487685
2014	19722349.4268231
2015	20051651.2973949
2016	21904910.8870129
2017	23386061.2335075
2018	23591812.3238958
2019	25164007.1374793
2020	27517267.4873363
2021	28898190.3779055