Bi-annual US dollars 1987-06-30 232 1987-12-31 236 1988-06-30 222 1988-12-31 168 1989-06-30 68 1989-12-31 47 1990-06-30 78 1990-12-31 66 1991-06-30 65 1991-12-31 71 1992-06-30 122 1992-12-31 127 1993-06-30 144 1993-12-31 114 1994-06-30 154 1994-12-31 192 1995-06-30 208 1995-12-31 163 1996-06-30 284 1996-12-31 216 1997-06-30 226 1997-12-31 179 1998-06-30 122 1998-12-31 45 1999-06-30 79