Bi-annual US dollars 1987-06-30 242 1987-12-31 264 1988-06-30 258 1988-12-31 253 1989-06-30 290 1989-12-31 284 1990-06-30 344 1990-12-31 224 1991-06-30 154 1991-12-31 183 1992-06-30 188 1992-12-31 167 1993-06-30 191 1993-12-31 263 1994-06-30 224 1994-12-31 333 1995-06-30 258 1995-12-31 180 1996-06-30 365 1996-12-31 382 1997-06-30 284 1997-12-31 327 1998-06-30 385 1998-12-31 296 1999-06-30 292