Bi-annual US dollars 1987-06-30 303 1987-12-31 272 1988-06-30 160 1988-12-31 387 1989-06-30 668 1989-12-31 684 1990-06-30 794 1990-12-31 511 1991-06-30 357 1991-12-31 450 1992-06-30 832 1992-12-31 333 1993-06-30 359 1993-12-31 263 1994-06-30 284 1994-12-31 174 1995-06-30 262 1995-12-31 290 1996-06-30 267 1996-12-31 212 1997-06-30 326 1997-12-31 301 1998-06-30 337 1998-12-31 434 1999-06-30 413