Year	current US$
1981	558.9630750233619
1982	507.6965335565483
1983	537.0880423633744
1984	484.51144423939996
1985	383.4655273599833
1986	411.27346327577465
1987	495.23171263157366
1988	522.6198077736962
1989	532.4620452753416
1990	574.0670293134161
1991	599.4854106257774
1992	579.8672774338397
1993	562.6760734026175
1994	555.7614339385594
1995	613.9733943256564
1996	604.6295490283297
1997	621.7077086820345
1998	570.6767687233462
1999	553.9627155753781
2000	578.0326037816776
2001	500.42073431585754
2002	495.29770374803275
2003	653.6583077295622
2004	796.3206596593241
2005	890.1511712213974
2006	949.6306938738098
2007	1013.46866378382
2008	991.8103007256718
2009	1082.3257153037423
2010	1236.1990356484946
2011	1340.1388931756342
2012	1343.0479555903662
2013	1327.0210725409318
2014	1343.3473415190335
2015	1236.4980330072044
2016	1167.6512966458645
2017	1313.1177535828706
2018	1257.0464206577083
2019	1228.5140262539376
2020	1113.0516491612384
2021	1232.3518205196692