Bi-annual US dollars 1987-06-30 364 1987-12-31 328 1988-06-30 278 1988-12-31 394 1989-06-30 428 1989-12-31 477 1990-06-30 290 1990-12-31 203 1991-06-30 109 1991-12-31 95 1992-06-30 162 1992-12-31 226 1993-06-30 225 1993-12-31 158 1994-06-30 193 1994-12-31 150 1995-06-30 80 1995-12-31 85 1996-06-30 90 1996-12-31 147 1997-06-30 105 1997-12-31 123 1998-06-30 215 1998-12-31 70 1999-06-30 172