Bi-annual	US dollars
1987-06-30	569
1987-12-31	615
1988-06-30	670
1988-12-31	1266
1989-06-30	814
1989-12-31	1187
1990-06-30	872
1990-12-31	506
1991-06-30	564
1991-12-31	530
1992-06-30	451
1992-12-31	533
1993-06-30	429
1993-12-31	489
1994-06-30	525
1994-12-31	554
1995-06-30	436
1995-12-31	557
1996-06-30	493
1996-12-31	940
1997-06-30	902
1997-12-31	1045
1998-06-30	569
1998-12-31	764
1999-06-30	372