Bi-annual US dollars 1987-06-30 261 1987-12-31 151 1988-06-30 193 1988-12-31 251 1989-06-30 237 1989-12-31 269 1990-06-30 239 1990-12-31 280 1991-06-30 60 1991-12-31 67 1992-06-30 76 1992-12-31 52 1993-06-30 44 1993-12-31 40 1994-06-30 42 1994-12-31 8 1995-06-30 11 1995-12-31 8 1996-06-30 9 1996-12-31 9 1997-06-30 7 1997-12-31 7 1998-06-30 12787 1998-12-31 13973 1999-06-30 12070