Bi-annual US dollars 1987-06-30 87 1987-12-31 175 1988-06-30 263 1988-12-31 78 1989-06-30 60 1989-12-31 398 1990-06-30 276 1990-12-31 214 1991-06-30 287 1991-12-31 355 1992-06-30 295 1992-12-31 317 1993-06-30 432 1993-12-31 75 1994-06-30 137 1994-12-31 20 1995-06-30 237 1995-12-31 366 1996-06-30 270 1996-12-31 106 1997-06-30 47 1997-12-31 117 1998-06-30 43 1998-12-31 305 1999-06-30 1178