Bi-annual	US dollars
1987-06-30	3190
1987-12-31	3468
1988-06-30	3327
1988-12-31	3150
1989-06-30	3468
1989-12-31	3625
1990-06-30	3683
1990-12-31	3581
1991-06-30	3554
1991-12-31	4242
1992-06-30	4879
1992-12-31	5310
1993-06-30	8503
1993-12-31	10138
1994-06-30	8773
1994-12-31	10304
1995-06-30	9348
1995-12-31	9015
1996-06-30	10023
1996-12-31	9683
1997-06-30	8967
1997-12-31	9057
1998-06-30	12018
1998-12-31	10387
1999-06-30	10640