Bi-annual US dollars 1987-06-30 19 1987-12-31 23 1988-06-30 27 1988-12-31 51 1989-06-30 37 1989-12-31 18 1990-06-30 9 1990-12-31 21 1991-06-30 8 1991-12-31 11 1992-06-30 30 1992-12-31 38 1993-06-30 68 1993-12-31 72 1994-06-30 94 1994-12-31 99 1995-06-30 116 1995-12-31 129 1996-06-30 99 1996-12-31 98 1997-06-30 110 1997-12-31 110 1998-06-30 127 1998-12-31 90 1999-06-30 106