The GSA Federal Credit appears to have been Earth's standard currency at the time of Brothers in Arms.
There are only a few indicators of the value of a GSA Federal Credit:
- Half a million of them was worth "lots and lots and lots" of Barrayaran Imperial Marks.
- Rent for keeping a shuttle at London's shuttleport was 140 GSA federals per diem.
- Brothers in Arms chapters 1,3,4,9