Year	current US$
1970	764088.365502137
1971	874853.321879364
1972	1066860.07966038
1973	1546377.47738619
1974	1642052.91712541
1975	1961165.93254143
1976	2193337.74580129
1977	2003996.66750728
1978	2218990.80776766
1979	2666905.35981139
1980	3115679.47093864
1981	2304966.27598387
1982	2413473.20324523
1983	2215567.55249983
1984	1903606.54192208
1985	2148052.48139833
1986	2578022.05660588
1987	2954806.75901702
1988	3386271.76705864
1989	4288675.22122763
1990	4626786.4156063
1991	3428332.44562667
1992	3234081.23440251
1993	3645392.10273278
1994	3544771.78639713
1995	3815493.04953326
1996	3955850.66398464
1997	3149570.9144009
1998	3509482.28489139
1999	3819947.79927705
2000	4035565.41227312
2001	3983647.19363977
2002	4007724.06326625
2003	4356222.7965672
2004	3266998.02066011
2005	3556777.20547136
2006	4788009.76058328
2007	7173182.68965225
2008	7926376.9781582
2009	7125732.4205205
2010	9371124.74064185
2011	8875476.85093386
2012	7507331.79482065
2013	5754748.85500183
2014	7482118.03737661
2015	6854988.96472535
2016	5818134.10620664
2017	5918670.4916411
2018	8863501.79875305
2019	5824764.67599267
2020	4605407.66816575
2021	3705649.04213819