Bi-annual	US dollars
1987-06-30	15944
1987-12-31	16649
1988-06-30	16915
1988-12-31	13589
1989-06-30	14116
1989-12-31	14829
1990-06-30	14796
1990-12-31	14411
1991-06-30	11284
1991-12-31	12654
1992-06-30	11576
1992-12-31	11647
1993-06-30	26988
1993-12-31	25924
1994-06-30	28086
1994-12-31	26249
1995-06-30	29527
1995-12-31	33844
1996-06-30	34744
1996-12-31	37570
1997-06-30	39835
1997-12-31	38612
1998-06-30	33911
1998-12-31	31634
1999-06-30	27624