Year	current US$
1970	682759.646314088
1971	970880.381279339
1972	1158081.37551807
1973	1829590.54876945
1974	1663338.67292406
1975	2984004.75861041
1976	3099645.20729715
1977	3507295.04755058
1978	3043448.46251269
1979	5130743.83819884
1980	5789559.30222711
1981	5639478.43575681
1982	8916556.60000047
1983	8464581.83483452
1984	5603039.62272207
1985	5369873.75555431
1986	6638543.65624062
1987	8193397.37735149
1988	7598895.65517238
1989	8356463.31826756
1990	3420604.75647192
1991	3670595.00023085
1992	3984192.00219116
1993	4462588.04416301
1994	4621607.33450625
1995	4964467.21008537
1996	5100690.04228973
1997	3924388.72616203
1998	3929090.18592748
1999	3938212.29108459
2000	4194473.51701154
2001	4618353.18289612
2002	4688648.91209525
2003	5857788.54824879
2004	3579161.2980222
2005	5255850.19166408
2006	7269485.77044971
2007	9657299.92268506
2008	10100921.00581
2009	8446363.85242367
2010	9300279.79756153
2011	8945726.28654668
2012	9644563.0936679
2013	9739467.96007749
2014	11370347.3844138
2015	6982366.38752405
2016	6193113.70495885
2017	6860746.5211549
2018	8520643.4003245
2019	8740739.04185009
2020	6829850.82953689
2021	6844236.81688548