Bi-annual	US dollars
1987-06-30	422
1987-12-31	477
1988-06-30	517
1988-12-31	653
1989-06-30	527
1989-12-31	669
1990-06-30	436
1990-12-31	749
1991-06-30	480
1991-12-31	329
1992-06-30	301
1992-12-31	291
1993-06-30	533
1993-12-31	504
1994-06-30	511
1994-12-31	483
1995-06-30	468
1995-12-31	442
1996-06-30	424
1996-12-31	449
1997-06-30	647
1997-12-31	342
1998-06-30	492
1998-12-31	536
1999-06-30	691