Bi-annual US dollars 1987-06-30 350 1987-12-31 374 1988-06-30 363 1988-12-31 372 1989-06-30 363 1989-12-31 314 1990-06-30 324 1990-12-31 397 1991-06-30 428 1991-12-31 336 1992-06-30 369 1992-12-31 320 1993-06-30 333 1993-12-31 324 1994-06-30 335 1994-12-31 329 1995-06-30 302 1995-12-31 285 1996-06-30 309 1996-12-31 337 1997-06-30 265 1997-12-31 247 1998-06-30 212 1998-12-31 283 1999-06-30 266