Year	constant 2015 US$
1991	6770000
1992	136890000
1993	96720000
1994	111620000
1995	236360000
1996	125390000
1997	159160000
1998	201530000
1999	211570000
2000	173650000
2001	237700000
2002	224120000
2003	512550000
2004	306280000