Bi-annual	US dollars
1987-06-30	1045
1987-12-31	1089
1988-06-30	928
1988-12-31	897
1989-06-30	741
1989-12-31	719
1990-06-30	523
1990-12-31	488
1991-06-30	423
1991-12-31	439
1992-06-30	369
1992-12-31	267
1993-06-30	294
1993-12-31	232
1994-06-30	228
1994-12-31	296
1995-06-30	455
1995-12-31	645
1996-06-30	564
1996-12-31	372
1997-06-30	178
1997-12-31	599
1998-06-30	829
1998-12-31	549
1999-06-30	446