Bi-annual	US dollars
1987-06-30	8101
1987-12-31	8878
1988-06-30	8197
1988-12-31	7677
1989-06-30	6602
1989-12-31	6153
1990-06-30	6250
1990-12-31	6408
1991-06-30	5638
1991-12-31	5432
1992-06-30	6244
1992-12-31	5646
1993-06-30	6739
1993-12-31	6417
1994-06-30	8509
1994-12-31	7675
1995-06-30	7885
1995-12-31	7888
1996-06-30	8099
1996-12-31	7795
1997-06-30	8262
1997-12-31	7850
1998-06-30	10829
1998-12-31	11563
1999-06-30	10807