Bi-annual	US dollars
1987-06-30	5273
1987-12-31	5402
1988-06-30	4729
1988-12-31	4862
1989-06-30	4849
1989-12-31	3770
1990-06-30	2084
1990-12-31	1299
1991-06-30	1127
1991-12-31	1653
1992-06-30	1871
1992-12-31	2138
1993-06-30	3151
1993-12-31	3216
1994-06-30	3472
1994-12-31	4207
1995-06-30	4260
1995-12-31	4324
1996-06-30	4103
1996-12-31	5302
1997-06-30	5819
1997-12-31	7042
1998-06-30	7164
1998-12-31	6327
1999-06-30	6277