Year	US Dollars adjusted for inflation)
1988	11013607979.2258
1989	11428209018.672
1990	12233334531.6455
1991	12486807780.9952
1992	12559770962.6654
1993	12711216782.5046
1994	12910485667.9483
1995	13371378628.0628
1996	13979023119.3827
1997	14471822572.7899
1998	15008511791.0467
1999	15734981143.0663
2000	16511320979.4706
2001	17501641753.9451
2002	18755381230.7524
2003	20046919269.2951
2004	21616251925.8856
2005	23383020790.5415
2006	24472803075.3726
2007	26544274428.1676
2008	28021886853.3599
2009	29530121806.73509
2010	31407908612.0943
2011	33890549126.65329
2012	35632866873.3754
2013	38220903729.4146
2014	40883041247.82339
2015	43728220561.9177
2016	46775259595.79841
2017	50098249469.47601