Year	current US$
1970	4005054.54282261
1971	5737922.86955729
1972	6482915.54274062
1973	8696533.52862398
1974	15632939.4179494
1975	25483719.6282455
1976	31490350.1912559
1977	37752694.6836284
1978	29776851.7639715
1979	42779277.6221947
1980	38257820.473276
1981	28151136.1126506
1982	20690809.4980007
1983	31708140.8916577
1984	25314027.8053634
1985	26477639.2599773
1986	26924508.8447127
1987	26486809.2957575
1988	19093854.9040615
1989	27398453.390826
1990	32248013.000014
1991	4809138.59133179
1992	4092971.68173191
1993	2889968.26809344
1994	2514650.80906053
1995	2155010.80505289
1996	2452002.24186848
1997	1920184.15623384
1998	1070374.65337205
1999	1455843.45745824
2000	2065691.23540883
2001	2013539.28901602
2002	1419474.68288559
2003	931072.149424352
2004	1250647.86463612
2005	1471887.67400314
2006	1434245.38888599
2007	3269503.55465534
2008	7688906.48141527
2009	4908807.86925815
2010	10440769.1207868
2011	25875749.9886193
2012	34321647.5093653
2013	25157010.4231433
2014	19862746.2035553
2015	11297542.3977155
2016	13897596.0742528
2017	23176502.8071736
2018	30416288.2185315
2019	19354353.5082382
2020	1161018.32966959
2021	2714217.43346233