Standard part cost at time of job release

We have a custom scrap report which shows total production value, scrap cost, and DMR reject cost for the date range selected. The cost values in this report are based on the standard cost in the PartCost table - specifically these columns: StdBurdenCost, StdLaborCost, StdMtlBurCost.

The problem is that if the standard cost changes for one or more parts, the report is inaccurate for jobs ran before that cost change. Is the standard cost information from the PartCost table stored in one of the job tables at the time that a job is created or released?

The JobAsmbl table’s TLE and LLE (“This Level” and “Lower Level Estimate”) fields hold the estimated costs for the job. Pretty sure they don’t get updated.