Bi-annual US dollars 1987-06-30 48 1987-12-31 47 1988-06-30 53 1988-12-31 47 1989-06-30 39 1989-12-31 39 1990-06-30 49 1990-12-31 48 1991-06-30 47 1991-12-31 71 1992-06-30 88 1992-12-31 80 1993-06-30 80 1993-12-31 75 1994-06-30 63 1994-12-31 55 1995-06-30 65 1995-12-31 68 1996-06-30 71 1996-12-31 55 1997-06-30 98 1997-12-31 97 1998-06-30 90 1998-12-31 116 1999-06-30 74