Bi-annual	US dollars
1987-06-30	1022
1987-12-31	779
1988-06-30	691
1988-12-31	736
1989-06-30	775
1989-12-31	618
1990-06-30	473
1990-12-31	363
1991-06-30	392
1991-12-31	417
1992-06-30	367
1992-12-31	315
1993-06-30	527
1993-12-31	554
1994-06-30	917
1994-12-31	925
1995-06-30	746
1995-12-31	983
1996-06-30	791
1996-12-31	849
1997-06-30	487
1997-12-31	494
1998-06-30	413
1998-12-31	305
1999-06-30	511