Year	current US$
1987	800000000
1988	1000000000
1989	1000000000
1990	1100000000
1991	1100000000
1992	2542000000
1993	492063492.06349206
1994	475770925.11013216
1995	473226352.9590924
1996	402271332.1055863
1997	698515343.3633764
1998	791853939.9062362
1999	646030037.2808331
2000	839310332.9379253
2001	1052049540.7393464
2002	1510915648.0224404
2003	2164778330.0798936
2004	2611579434.923576
2005	3479854809.4373865
2006	4687339491.916859
2007	5355722326.454034
2008	5244782976.236852
2009	5457998280.701755
2010	6355698947.368421
2011	7380350877.192983
2012	8762456140.350878
2013	11013684210.526316
2014	13507719298.245613
2015	13031142857.142857
2016	13758857142.857143
2017	15867714285.714285
2018	17958000000
2019	21158285714.285713
2020	23424571428.57143
2021	25537714285.714287
2022	27034857142.857143