Bi-annual US dollars 1987-06-30 111 1987-12-31 125 1988-06-30 113 1988-12-31 103 1989-06-30 48 1989-12-31 32 1990-06-30 40 1990-12-31 46 1991-06-30 37 1991-12-31 47 1992-06-30 114 1992-12-31 98 1993-06-30 48 1993-12-31 52 1994-06-30 76 1994-12-31 77 1995-06-30 102 1995-12-31 109 1996-06-30 138 1996-12-31 87 1997-06-30 126 1997-12-31 283 1998-06-30 328 1998-12-31 190 1999-06-30 221