Bi-annual	US dollars
1987-06-30	1117
1987-12-31	1351
1988-06-30	1306
1988-12-31	1025
1989-06-30	1057
1989-12-31	710
1990-06-30	612
1990-12-31	712
1991-06-30	616
1991-12-31	760
1992-06-30	929
1992-12-31	1436
1993-06-30	813
1993-12-31	1385
1994-06-30	1063
1994-12-31	1522
1995-06-30	1942
1995-12-31	1597
1996-06-30	1756
1996-12-31	2450
1997-06-30	2251
1997-12-31	4286
1998-06-30	4063
1998-12-31	4010
1999-06-30	2934