Year	current US$
1981	1014.755198141921
1982	1091.506001536
1983	1131.9076034619254
1984	839.1911291952991
1985	838.5881222543892
1986	1129.1480473418253
1987	1133.7122186017475
1988	1140.6204341017356
1989	1140.9246646744639
1990	844.4697332895769
1991	945.4119450055521
1992	516.9776988383469
1993	300.5445347367035
1994	344.0652998407189
1995	534.2650217423984
1996	519.5134207615379
1997	435.19733236033187
1998	416.02696526992514
1999	390.5277873679577
2000	405.78750298890117
2001	441.6950537719996
2002	484.53039007650875
2003	553.9706225734943
2004	667.3763630377324
2005	802.1376366487318
2006	998.1422328872187
2007	1243.7733564631533
2008	1645.4270226650347
2009	1321.1734136035448
2010	1873.3114622791468
2011	2607.85006724856
2012	3360.8244082311994
2013	3532.178597657349
2014	3219.9675904986425
2015	2891.2734339202207
2016	2700.438230201059
2017	2434.239493006056
2018	2918.5955623001423
2019	3149.0038489799626
2020	2968.889172748075
2021	2792.1669629659846