Bi-annual	US dollars
1987-06-30	1032
1987-12-31	1030
1988-06-30	858
1988-12-31	682
1989-06-30	660
1989-12-31	534
1990-06-30	525
1990-12-31	552
1991-06-30	425
1991-12-31	407
1992-06-30	500
1992-12-31	533
1993-06-30	654
1993-12-31	624
1994-06-30	498
1994-12-31	574
1995-06-30	697
1995-12-31	557
1996-06-30	799
1996-12-31	709
1997-06-30	1228
1997-12-31	1820
1998-06-30	1099
1998-12-31	762
1999-06-30	661