Bi-annual	US dollars
1987-06-30	1192
1987-12-31	1319
1988-06-30	1538
1988-12-31	915
1989-06-30	1350
1989-12-31	1355
1990-06-30	1716
1990-12-31	1804
1991-06-30	1623
1991-12-31	1787
1992-06-30	1958
1992-12-31	1265
1993-06-30	1131
1993-12-31	1012
1994-06-30	1199
1994-12-31	2453
1995-06-30	2378
1995-12-31	1420
1996-06-30	928
1996-12-31	889
1997-06-30	785
1997-12-31	1357
1998-06-30	1619
1998-12-31	1393
1999-06-30	1053