Bi-annual	US dollars
1987-06-30	1772
1987-12-31	1987
1988-06-30	1666
1988-12-31	1546
1989-06-30	1468
1989-12-31	1061
1990-06-30	809
1990-12-31	646
1991-06-30	571
1991-12-31	558
1992-06-30	533
1992-12-31	480
1993-06-30	429
1993-12-31	378
1994-06-30	394
1994-12-31	383
1995-06-30	453
1995-12-31	781
1996-06-30	601
1996-12-31	625
1997-06-30	775
1997-12-31	860
1998-06-30	1912
1998-12-31	1572
1999-06-30	1132