Bi-annual US dollars 1987-06-30 226 1987-12-31 225 1988-06-30 500 1988-12-31 118 1989-06-30 250 1989-12-31 250 1990-06-30 333 1990-12-31 201 1991-06-30 295 1991-12-31 194 1992-06-30 316 1992-12-31 147 1993-06-30 398 1993-12-31 152 1994-06-30 401 1994-12-31 299 1995-06-30 506 1995-12-31 509 1996-06-30 416 1996-12-31 142 1997-06-30 243 1997-12-31 137 1998-06-30 263 1998-12-31 53 1999-06-30 456