Controllers, outsourced accounting partners and QoE analysts keep evaluating "AI for technical accounting" tools and keep going back to spreadsheets. The reason is accountability: their name is on the workpapers, and the vendor isn't in the room when the auditor asks how an allocation was determined.
The audit problem with black boxes
- Unverifiable rationale: "The model suggested this split" is not an audit workpaper.
- Re-verification overhead: if someone has to re-read the whole contract to check the tool, it added a step instead of removing one.
- Reproducibility: a calculation that cannot be re-run to the same cent cannot be a reliable audit schedule.
Worked example: what "ties out" means
A $100,000 contract bundles three obligations. Total SSP is $180,000, so the $80,000 discount is spread in proportion.
| Obligation | SSP | Engine allocation |
|---|---|---|
| Implementation | $30,000 | $16,666.67 |
| Premium support | $30,000 | $16,666.67 |
| Platform subscription | $120,000 | $66,666.66 |
| Total | $180,000 | $100,000.00 |
Round each line on its own and the three allocations sum to $100,000.01. The engine's allocation sums to exactly $100,000.00 because one obligation absorbs the rounding residual. The exported workbook carries the page and excerpt for each obligation plus a SHA-256 hash, so re-running the same inputs gives the same cents.
What makes it reviewable is the order of operations: a human confirms the obligations and prices, the arithmetic is integer and deterministic, and the evidence (page plus verbatim excerpt; on uploaded text-layer PDFs, a highlight box on the cited line) travels with the number.
Try your own numbers in the free SSP allocation calculator.
