Bi-annual	US dollars
1987-06-30	12336
1987-12-31	14451
1988-06-30	13874
1988-12-31	14469
1989-06-30	14893
1989-12-31	16891
1990-06-30	17440
1990-12-31	19386
1991-06-30	14297
1991-12-31	14423
1992-06-30	14537
1992-12-31	18981
1993-06-30	26379
1993-12-31	27381
1994-06-30	27977
1994-12-31	28128
1995-06-30	29324
1995-12-31	27648
1996-06-30	32271
1996-12-31	26945
1997-06-30	29480
1997-12-31	31205
1998-06-30	38111
1998-12-31	38718
1999-06-30	40888