Bi-annual	US dollars
1987-06-30	489
1987-12-31	630
1988-06-30	616
1988-12-31	792
1989-06-30	426
1989-12-31	376
1990-06-30	481
1990-12-31	268
1991-06-30	350
1991-12-31	247
1992-06-30	424
1992-12-31	342
1993-06-30	462
1993-12-31	646
1994-06-30	699
1994-12-31	458
1995-06-30	482
1995-12-31	438
1996-06-30	379
1996-12-31	354
1997-06-30	471
1997-12-31	191
1998-06-30	163
1998-12-31	130
1999-06-30	131