Bi-annual US dollars 1987-06-30 132 1987-12-31 245 1988-06-30 121 1988-12-31 141 1989-06-30 290 1989-12-31 331 1990-06-30 237 1990-12-31 334 1991-06-30 232 1991-12-31 269 1992-06-30 171 1992-12-31 123 1993-06-30 156 1993-12-31 338 1994-06-30 188 1994-12-31 171 1995-06-30 177 1995-12-31 118 1996-06-30 332 1996-12-31 330 1997-06-30 745 1997-12-31 997 1998-06-30 1439 1998-12-31 439 1999-06-30 413