Bi-annual	US dollars
1987-06-30	3414
1987-12-31	4361
1988-06-30	3928
1988-12-31	3661
1989-06-30	3913
1989-12-31	4191
1990-06-30	4780
1990-12-31	4145
1991-06-30	3441
1991-12-31	3790
1992-06-30	3296
1992-12-31	3892
1993-06-30	4769
1993-12-31	4814
1994-06-30	6392
1994-12-31	4202
1995-06-30	5770
1995-12-31	6062
1996-06-30	5435
1996-12-31	5472
1997-06-30	4550
1997-12-31	7361
1998-06-30	6974
1998-12-31	7901
1999-06-30	8471