Bi-annual	US dollars
1987-06-30	2016
1987-12-31	530
1988-06-30	576
1988-12-31	557
1989-06-30	428
1989-12-31	701
1990-06-30	326
1990-12-31	370
1991-06-30	352
1991-12-31	497
1992-06-30	384
1992-12-31	570
1993-06-30	474
1993-12-31	482
1994-06-30	892
1994-12-31	1044
1995-06-30	482
1995-12-31	523
1996-06-30	1105
1996-12-31	1428
1997-06-30	1096
1997-12-31	448
1998-06-30	1187
1998-12-31	1225
1999-06-30	683