Year	current US$
1994	2171800000
1995	2137720000
1996	6021200000
1997	8428300000
1998	11445600000
1999	2869900000
2000	4386400000
2001	1629500000
2002	660100000
2004	1092600000
2005	3262900000
2006	6286390000
2007	12439600000
2008	13291380000
2009	11893860000
2012	25574940000
2013	18425900000
2014	39382040000
2015	14758200000
2018	4087500000
2020	2357860000