Bi-annual US dollars 1987-06-30 289 1987-12-31 277 1988-06-30 263 1988-12-31 278 1989-06-30 251 1989-12-31 197 1990-06-30 206 1990-12-31 189 1991-06-30 180 1991-12-31 144 1992-06-30 131 1992-12-31 95 1993-06-30 68 1993-12-31 38 1994-06-30 68 1994-12-31 11 1995-06-30 40 1995-12-31 138 1996-06-30 132 1996-12-31 144 1997-06-30 165 1997-12-31 171 1998-06-30 168 1998-12-31 156 1999-06-30 139