Year	constant 2015 US$
1991	5430000
1992	120270000
1993	52370000
1994	83330000
1995	88200000
1996	100340000
1997	124280000
1998	152370000
1999	158450000
2000	160440000
2001	191750000
2002	127550000
2003	157190000
2004	199700000