Bi-annual	US dollars
1987-06-30	1017
1987-12-31	1385
1988-06-30	1289
1988-12-31	1710
1989-06-30	1701
1989-12-31	1324
1990-06-30	1191
1990-12-31	1607
1991-06-30	1333
1991-12-31	2157
1992-06-30	2034
1992-12-31	1426
1993-06-30	1289
1993-12-31	848
1994-06-30	965
1994-12-31	1122
1995-06-30	962
1995-12-31	823
1996-06-30	867
1996-12-31	935
1997-06-30	973
1997-12-31	1247
1998-06-30	1079
1998-12-31	1298
1999-06-30	1411