Bi-annual	US dollars
1987-06-30	1529
1987-12-31	2006
1988-06-30	2093
1988-12-31	2517
1989-06-30	1873
1989-12-31	2764
1990-06-30	2248
1990-12-31	2364
1991-06-30	1662
1991-12-31	1565
1992-06-30	1536
1992-12-31	1247
1993-06-30	1564
1993-12-31	1689
1994-06-30	1656
1994-12-31	1460
1995-06-30	1365
1995-12-31	1532
1996-06-30	1332
1996-12-31	1423
1997-06-30	1582
1997-12-31	1596
1998-06-30	1466
1998-12-31	1298
1999-06-30	1570