Bi-annual	US dollars
1987-06-30	10728
1987-12-31	8027
1988-06-30	8635
1988-12-31	8774
1989-06-30	9228
1989-12-31	8543
1990-06-30	9229
1990-12-31	8978
1991-06-30	7808
1991-12-31	7779
1992-06-30	7528
1992-12-31	6360
1993-06-30	7487
1993-12-31	7938
1994-06-30	9336
1994-12-31	21193
1995-06-30	26717
1995-12-31	26780
1996-06-30	36369
1996-12-31	44870
1997-06-30	46894
1997-12-31	57363
1998-06-30	67952
1998-12-31	54882
1999-06-30	53441