Year	current US$
1991	613600000
1992	13400000
1993	1047700000
1994	314800000
1995	1008300000
1996	1553100000
1997	1019200000
1998	922300000
1999	2235400000
2000	1828900000
2001	240000000
2002	10500000
2003	844770000
2004	2362270000
2005	579100000
2006	4798980000
2007	9344850000
2008	12415880000
2009	21222600000
2010	29608760000
2011	21011250000
2012	8904400000
2013	2952700000
2014	2816630000
2015	2086940000
2016	1686930000
2017	1311630000
2018	1639510000
2019	856350000
2020	3321000000
2021	1621240000
2022	2503340000