Bi-annual	US dollars
1987-06-30	2299
1987-12-31	2470
1988-06-30	2120
1988-12-31	2535
1989-06-30	2438
1989-12-31	3785
1990-06-30	3448
1990-12-31	3052
1991-06-30	2051
1991-12-31	2170
1992-06-30	2190
1992-12-31	1895
1993-06-30	2360
1993-12-31	2380
1994-06-30	2343
1994-12-31	2355
1995-06-30	1823
1995-12-31	2201
1996-06-30	2234
1996-12-31	2558
1997-06-30	2728
1997-12-31	3597
1998-06-30	3233
1998-12-31	2235
1999-06-30	2498