Bi-annual	US dollars
1987-06-30	3583
1987-12-31	4470
1988-06-30	3281
1988-12-31	3498
1989-06-30	3465
1989-12-31	3320
1990-06-30	3992
1990-12-31	3838
1991-06-30	3485
1991-12-31	3426
1992-06-30	3709
1992-12-31	3598
1993-06-30	4514
1993-12-31	4387
1994-06-30	4875
1994-12-31	5035
1995-06-30	5189
1995-12-31	6256
1996-06-30	6661
1996-12-31	7582
1997-06-30	9998
1997-12-31	12221
1998-06-30	9734
1998-12-31	10566
1999-06-30	8519