Bi-annual	US dollars
1987-06-30	384
1987-12-31	428
1988-06-30	346
1988-12-31	416
1989-06-30	519
1989-12-31	347
1990-06-30	630
1990-12-31	351
1991-06-30	465
1991-12-31	598
1992-06-30	348
1992-12-31	309
1993-06-30	540
1993-12-31	613
1994-06-30	875
1994-12-31	763
1995-06-30	848
1995-12-31	977
1996-06-30	963
1996-12-31	1335
1997-06-30	1539
1997-12-31	2312
1998-06-30	2971
1998-12-31	6302
1999-06-30	4689