Bi-annual	US dollars
1987-06-30	4999
1987-12-31	7006
1988-06-30	6073
1988-12-31	5704
1989-06-30	4679
1989-12-31	4481
1990-06-30	4554
1990-12-31	5202
1991-06-30	4955
1991-12-31	4853
1992-06-30	4796
1992-12-31	5069
1993-06-30	6577
1993-12-31	6703
1994-06-30	7711
1994-12-31	7039
1995-06-30	7058
1995-12-31	5658
1996-06-30	7315
1996-12-31	7011
1997-06-30	12680
1997-12-31	7514
1998-06-30	8116
1998-12-31	6824
1999-06-30	6042