Year	US Dollars adjusted for inflation)
1990	22325675014.6271
1991	22169395298.4412
1992	17159111873.5004
1993	13195357108.1839
1994	10595871755.3639
1995	9345558792.93588
1996	9467051075.91296
1997	10016140087.9139
1998	11017754124.5694
1999	11833067993.8748
2000	13146538452.8659
2001	14448045759.6996
2002	15979538494.8706
2003	17769246844.1912
2004	19581710093.0734
2005	24751281715.9126
2006	33290473786.69379
2007	41629404406.7868
2008	46113899018.7892
2009	50453518392.5171
2010	52902703376.1056
2011	52937578302.43831
2012	54102205124.8452
2013	57238335961.2495
2014	58383102680.4744
2015	59025316698.50349
2016	57195531761.59171
2017	57252727186.91261