Year	constant 2015 US$
1990	538910000
1991	2674930000
1992	1891870000
1993	1359420000
1994	1406470000
1995	872550000
1996	1456980000
1997	1367340000
1998	2297470000
1999	2377220000
2000	2536030000
2001	2794760000
2002	1893640000
2003	1861870000
2004	2269090000
2011	230000