Year	constant 2015 US$
1990	382300000
1991	740650000
1992	1018420000
1993	719180000
1994	609130000
1995	717240000
1996	680120000
1997	446600000
1998	692790000
1999	853080000
2000	845880000
2001	797400000
2002	719530000
2003	475830000
2004	498150000