Bi-annual US dollars 1987-06-30 52 1987-12-31 66 1988-06-30 84 1988-12-31 119 1989-06-30 153 1989-12-31 60 1990-06-30 84 1990-12-31 122 1991-06-30 94 1991-12-31 129 1992-06-30 143 1992-12-31 89 1993-06-30 140 1993-12-31 189 1994-06-30 177 1994-12-31 181 1995-06-30 157 1995-12-31 160 1996-06-30 110 1996-12-31 77 1997-06-30 336 1997-12-31 341 1998-06-30 340 1998-12-31 100 1999-06-30 284