Bi-annual US dollars 1987-06-30 316 1987-12-31 370 1988-06-30 374 1988-12-31 401 1989-06-30 177 1989-12-31 406 1990-06-30 389 1990-12-31 417 1991-06-30 118 1991-12-31 112 1992-06-30 114 1992-12-31 79 1993-06-30 77 1993-12-31 281 1994-06-30 335 1994-12-31 238 1995-06-30 248 1995-12-31 324 1996-06-30 483 1996-12-31 543 1997-06-30 517 1997-12-31 564 1998-06-30 779 1998-12-31 677 1999-06-30 705