Bi-annual US dollars 1987-06-30 16 1987-12-31 32 1988-06-30 46 1988-12-31 43 1989-06-30 60 1989-12-31 69 1990-06-30 54 1990-12-31 46 1991-06-30 47 1991-12-31 47 1992-06-30 51 1992-12-31 68 1993-06-30 81 1993-12-31 151 1994-06-30 151 1994-12-31 167 1995-06-30 186 1995-12-31 161 1996-06-30 196 1996-12-31 243 1997-06-30 246 1997-12-31 275 1998-06-30 372 1998-12-31 369 1999-06-30 442