Bi-annual	US dollars
1987-06-30	4741
1987-12-31	4150
1988-06-30	5014
1988-12-31	5919
1989-06-30	4719
1989-12-31	4921
1990-06-30	4210
1990-12-31	3830
1991-06-30	3849
1991-12-31	3685
1992-06-30	4091
1992-12-31	3998
1993-06-30	4444
1993-12-31	5115
1994-06-30	5481
1994-12-31	4367
1995-06-30	4691
1995-12-31	5966
1996-06-30	5691
1996-12-31	6579
1997-06-30	6229
1997-12-31	7076
1998-06-30	6369
1998-12-31	7887
1999-06-30	11563