HOW THE SOURCE CHECKER WORKS / PRACTICE SET 01

Raw holds all seven original CSV fields as text. Source build applies the
supplied business rules to dates, mapped categories, signed cents, exact
copies, ID conflicts and row disposition. Its calculations do not read AI
output or the separate answer CSVs. A raw-file parser supplied only the
fixed source-ID-to-slot index, not expected totals or categories.

Checks compares the included source rows with AI output in their fixed
slots: included count, expected IDs, normalized fields, extras/excluded
records, signed sales/refunds/net, and monthly/category counts and net.
Each group must agree independently and reconcile to the included total.
A count or grand total alone cannot establish that each line is correct.

The row order is part of this exercise. A correct file in another order
will conservatively return REVIEW. New IDs or changed raw keys require an
index rebuild. Capacity is A7:G2006 on Raw and AI output; reporting tables
cover January-March only. Other exports need adapted mapping and rules.

Invalid/missing dates stay in quarantine, not guessed from neighbouring
rows. A comparison MATCH does not resolve quarantine or certify the
underlying business system. Filter Source build on Disposition=QUARANTINE
to inspect the excluded records and reasons.

VERIFICATION SCOPE
The source workbook was recalculated and tested in Windows Excel using
English number/date conventions, including deliberate changes and restores.
Exact Excel build, other apps and other regional settings were not verified.
The public version changes editor/path and attached add-in metadata for
privacy. Worksheet parts, formulas, cached values, styles, tables and
worksheet relationships are unchanged. No AI add-in is attached.
It passed ZIP/XML checks and opened in desktop Excel without a recovery or
add-in prompt, showing four MATCH results. This was an open check, not a
repeat calculation test. This is one synthetic exercise, not a general accuracy or
speed benchmark. The source business-system accuracy is outside its scope.