Bi-annual	US dollars
1987-06-30	753
1987-12-31	1355
1988-06-30	1308
1988-12-31	1031
1989-06-30	1759
1989-12-31	1121
1990-06-30	2023
1990-12-31	1285
1991-06-30	1229
1991-12-31	1373
1992-06-30	1671
1992-12-31	1794
1993-06-30	1169
1993-12-31	2142
1994-06-30	2639
1994-12-31	2408
1995-06-30	2617
1995-12-31	2093
1996-06-30	2528
1996-12-31	1731
1997-06-30	1509
1997-12-31	1334
1998-06-30	1152
1998-12-31	561
1999-06-30	4404