Bi-annual US dollars 1987-06-30 160 1987-12-31 136 1988-06-30 131 1988-12-31 78 1989-06-30 71 1989-12-31 39 1990-06-30 91 1990-12-31 75 1991-06-30 39 1991-12-31 32 1992-06-30 78 1992-12-31 121 1993-06-30 108 1993-12-31 130 1994-06-30 293 1994-12-31 438 1995-06-30 372 1995-12-31 433 1996-06-30 452 1996-12-31 402 1997-06-30 521 1997-12-31 260 1998-06-30 272 1998-12-31 215 1999-06-30 191