Bi-annual	US dollars
1987-06-30	43142
1987-12-31	43488
1988-06-30	41391
1988-12-31	40832
1989-06-30	38560
1989-12-31	34635
1990-06-30	31352
1990-12-31	30664
1991-06-30	28433
1991-12-31	30389
1992-06-30	31036
1992-12-31	29438
1993-06-30	34505
1993-12-31	36301
1994-06-30	37241
1994-12-31	40126
1995-06-30	41218
1995-12-31	44490
1996-06-30	45004
1996-12-31	50843
1997-06-30	56358
1997-12-31	61801
1998-06-30	63094
1998-12-31	63568
1999-06-30	57266