Bi-annual	US dollars
1987-06-30	729
1987-12-31	745
1988-06-30	854
1988-12-31	1206
1989-06-30	845
1989-12-31	795
1990-06-30	886
1990-12-31	791
1991-06-30	675
1991-12-31	667
1992-06-30	573
1992-12-31	436
1993-06-30	750
1993-12-31	454
1994-06-30	586
1994-12-31	515
1995-06-30	708
1995-12-31	861
1996-06-30	1039
1996-12-31	1371
1997-06-30	830
1997-12-31	1114
1998-06-30	934
1998-12-31	716
1999-06-30	585