It is a Crystal work file, populated either from printing a work ticket or by the Crystal File Regeneration. If you run the Crystal File Regeneration with the option set to ""history"" or ""both"", it will get repopulated, probably back to the same size. This file is used for reporting as well as work ticket printing.
In JobOps 4.40 R4, the Crystal File Regeneration allows for a date range for the history. Note that R4 is not just bug fixes, but includes moving some functions from legacy to framework ( including the work ticket printing, so forms have to be recustomized), so either pilot the hell out of it before going live or wait for R4M (or N, or maybe Z).