Bi-annual US dollars 1987-06-30 74 1987-12-31 87 1988-06-30 72 1988-12-31 72 1989-06-30 59 1989-12-31 66 1990-06-30 59 1990-12-31 66 1991-06-30 57 1991-12-31 69 1992-06-30 70 1992-12-31 38 1993-06-30 35 1993-12-31 37 1994-06-30 40 1994-12-31 39 1995-06-30 43 1995-12-31 43 1996-06-30 40 1996-12-31 39 1997-06-30 35 1997-12-31 36 1998-06-30 37 1998-12-31 48 1999-06-30 44