Bi-annual	US dollars
1987-06-30	1330
1987-12-31	1381
1988-06-30	1296
1988-12-31	1582
1989-06-30	1577
1989-12-31	1261
1990-06-30	1170
1990-12-31	1067
1991-06-30	1025
1991-12-31	736
1992-06-30	744
1992-12-31	724
1993-06-30	734
1993-12-31	1009
1994-06-30	969
1994-12-31	876
1995-06-30	1017
1995-12-31	972
1996-06-30	921
1996-12-31	846
1997-06-30	855
1997-12-31	755
1998-06-30	717
1998-12-31	729
1999-06-30	697