Bi-annual	US dollars
1987-06-30	448
1987-12-31	494
1988-06-30	674
1988-12-31	752
1989-06-30	794
1989-12-31	601
1990-06-30	717
1990-12-31	621
1991-06-30	577
1991-12-31	661
1992-06-30	757
1992-12-31	630
1993-06-30	801
1993-12-31	845
1994-06-30	914
1994-12-31	968
1995-06-30	1029
1995-12-31	1101
1996-06-30	1144
1996-12-31	1204
1997-06-30	1150
1997-12-31	933
1998-06-30	970
1998-12-31	1022
1999-06-30	984