Year	current US$
1997	38953480000
1998	62954000000
1999	68147740000.00001
2000	60680690000
2001	46337810000
2002	42845350000
2003	58284740000
2004	70240380000
2005	66973399999.99999
2006	104187320000
2007	132238540000.00002
2008	68876020000
2009	98247200000
2010	81996700000
2011	61689890000
2012	65519040000
2013	79177900000
2014	57774190000
2015	59837190000
2016	57255223904.945595
2017	75589628811.63919
2018	61933604857.411