Year	current US$
1971	8345.41808660103
1972	34580.7542695223
1973	110027.304681648
1974	896455.226197897
1975	1133173.87470335
1976	1509337.72873866
1977	1514018.07142633
1978	1934429.83562648
1979	5378449.11693348
1980	7307458.70928897
1981	4422727.82166676
1982	3272580.99937598
1983	6487859.17408816
1984	10767395.0013152
1985	10991298.5322934
1986	3938578.84877979
1987	5592109.07050037
1988	3154826.01809293
1989	4624729.16052431
1990	7493659.59686426
1991	4100172.98381785
1992	4727620.99116182
1993	3957185.94421752
1994	4042821.06047487
1995	4961838.13385095
1996	4620062.30759463
1997	3711455.03707459
1998	3636478.53799532
1999	7504111.34635059
2000	10463522.69077
2001	6762563.50315463
2002	6753968.7525366
2003	6317168.0532731
2004	7135856.45704103
2005	11992017.0204549
2006	14740968.9311271
2007	14109026.3844419
2008	16514670.0974914
2009	8136121.56407969
2010	11570512.5487145
2011	19653285.1691854
2012	17908828.2576671
2013	14984024.4791038
2014	12117456.3802484
2015	4528792.20531979
2016	3356822.952013
2017	5052545.17133147
2018	8581140.86244514
2019	10455628.4198684
2020	5280459.73961023
2021	14086557.2148793