Bi-annual	US dollars
1987-06-30	231
1987-12-31	247
1988-06-30	225
1988-12-31	253
1989-06-30	250
1989-12-31	268
1990-06-30	290
1990-12-31	340
1991-06-30	279
1991-12-31	374
1992-06-30	350
1992-12-31	356
1993-06-30	377
1993-12-31	334
1994-06-30	511
1994-12-31	502
1995-06-30	565
1995-12-31	529
1996-06-30	536
1996-12-31	582
1997-06-30	562
1997-12-31	711
1998-06-30	724
1998-12-31	561
1999-06-30	517