Bi-annual US dollars 1987-06-30 321 1987-12-31 242 1988-06-30 464 1988-12-31 468 1989-06-30 547 1989-12-31 603 1990-06-30 729 1990-12-31 413 1991-06-30 269 1991-12-31 325 1992-06-30 291 1992-12-31 374 1993-06-30 546 1993-12-31 313 1994-06-30 361 1994-12-31 127 1995-06-30 76 1995-12-31 116 1996-06-30 96 1996-12-31 92 1997-06-30 67 1997-12-31 114 1998-06-30 252 1998-12-31 180 1999-06-30 150