Bi-annual	US dollars
1987-06-30	648
1987-12-31	770
1988-06-30	708
1988-12-31	741
1989-06-30	645
1989-12-31	630
1990-06-30	595
1990-12-31	621
1991-06-30	611
1991-12-31	682
1992-06-30	632
1992-12-31	542
1993-06-30	617
1993-12-31	720
1994-06-30	748
1994-12-31	829
1995-06-30	985
1995-12-31	1000
1996-06-30	1339
1996-12-31	1477
1997-06-30	1479
1997-12-31	1576
1998-06-30	1424
1998-12-31	1341
1999-06-30	1020