Bi-annual US dollars 1987-06-30 5 1987-12-31 8 1988-06-30 7 1988-12-31 33 1989-06-30 34 1989-12-31 60 1990-06-30 47 1990-12-31 46 1991-06-30 58 1991-12-31 67 1992-06-30 70 1992-12-31 76 1993-06-30 138 1993-12-31 112 1994-06-30 108 1994-12-31 72 1995-06-30 76 1995-12-31 81 1996-06-30 85 1996-12-31 82 1997-06-30 58 1997-12-31 7 1998-06-30 2 1998-12-31 0 1999-06-30 0