Bi-annual US dollars 1987-06-30 176 1987-12-31 175 1988-06-30 113 1988-12-31 228 1989-06-30 260 1989-12-31 245 1990-06-30 218 1990-12-31 176 1991-06-30 143 1991-12-31 172 1992-06-30 169 1992-12-31 150 1993-06-30 249 1993-12-31 328 1994-06-30 387 1994-12-31 466 1995-06-30 624 1995-12-31 546 1996-06-30 631 1996-12-31 609 1997-06-30 527 1997-12-31 469 1998-06-30 509 1998-12-31 829 1999-06-30 702