Bi-annual US dollars 1987-06-30 60 1987-12-31 66 1988-06-30 56 1988-12-31 47 1989-06-30 40 1989-12-31 50 1990-06-30 44 1990-12-31 44 1991-06-30 63 1991-12-31 84 1992-06-30 49 1992-12-31 55 1993-06-30 146 1993-12-31 92 1994-06-30 42 1994-12-31 97 1995-06-30 67 1995-12-31 84 1996-06-30 117 1996-12-31 257 1997-06-30 77 1997-12-31 250 1998-06-30 128 1998-12-31 87 1999-06-30 112