Bi-annual US dollars 1987-06-30 163 1987-12-31 170 1988-06-30 167 1988-12-31 130 1989-06-30 259 1989-12-31 226 1990-06-30 99 1990-12-31 15 1991-06-30 287 1991-12-31 54 1992-06-30 61 1992-12-31 8 1993-06-30 86 1993-12-31 126 1994-06-30 279 1994-12-31 106 1995-06-30 247 1995-12-31 113 1996-06-30 62 1996-12-31 276 1997-06-30 126 1997-12-31 380 1998-06-30 177 1998-12-31 68 1999-06-30 224