Hidden formulae
Rates can be typed over formulas and logic can sit on hidden tabs.
CAI Controlled Conversion
When a spreadsheet becomes too critical to remain a spreadsheet.
Preserve the logic that matters, add the controls the process now needs, and transfer trust only after the new application reproduces historical periods to the unit.
The problem
Critical logic, without the controls a system would have.
The risk is not the spreadsheet itself. It is the point at which a recurring calculation becomes material while ownership, change control and evidence remain file-dependent.
Broad access
Anyone with the file may be able to change logic, inputs or outputs.
Weak change evidence
The latest file is visible, but what changed and why can be difficult to reconstruct.
Key-person dependency
Critical conventions often live with one analyst rather than in an owned specification.
Equivalence Protocol
Prove the number before transferring trust.
The method separates specification, controlled implementation, historical proof and operating handover. Differences are investigated and signed; they are never silently absorbed.
- 01Specify
Formulas, hidden tabs and unwritten conventions are written in plain language and signed.
- 02Build
The logic is implemented with sign-in, roles, approvals, versioning and an audit trail.
- 03Replay and reconcile
Past month-ends run through both implementations. Differences are explained, not absorbed.
- 04Evidence and handover
The proof, controls, runbook and source are handed over into a client-owned operating model.
Sign-in and roles
Your identity provider decides who can do what. Nobody approves their own work.
Data intake checks
The monthly report must reconcile to the source record before anything is computed.
Maker-checker
Judgements and overrides carry a reason, evidence and an approver.
Rule versioning
Rates and adjustments are versioned, approved and effective from a defined period.
Sign-off and lock
The accountable review is recorded and the period can be locked.
Audit evidence
Actions, including refused attempts, remain traceable in the evidence trail.
Northfield reference demo
One allowance, shown under three reporting frameworks.
Northfield Industrial Components is fictional and all data is synthetic. The reference case shows an allowance process moving from an analyst-owned workbook into a controlled month-end application.
The equivalence proof
Trusted only after it reproduces history.
Twenty-four historical month-ends are replayed through the old workbook and the controlled application. Each difference is traced, resolved or documented, and signed by the sheet owner.
- Old workbook
- $4,617,728
- Controlled application
- $4,617,728
- Difference
- $0
Reference demonstration 2
Sales incentive calculation.
A second synthetic case applies the same Equivalence Protocol to a monthly incentive payout, showing that Controlled Conversion is a method rather than an allowance-specific product.
120 paid employee-months become the acceptance test
- Historical oracle
- Payroll amounts actually paid, supported by the archived workbook.
- Final replay
- 119 exact matches + 1 signed approved legacy error.
- Outcome
- 120 of 120 explained before trust transfers.
Explore the sales incentive demo
2:24 reference video + interactive demo
Where this applies
The same protocol for other critical workbooks.
Northfield is the reference build. The method applies where a recurring calculation is relied on, the logic is sufficiently specifiable and the cost of an uncontrolled number is material.
Receivables allowance and credit holds
- Usual owner
- Finance and credit control
- What can go wrong
- A misstated allowance, and shipments to customers who should be on hold.
- Forcing function
- A controls observation or an unexpected write-off.
Lenders and NBFCs
Borrowing covenant tracking and lender certificates
- Usual owner
- Treasury and CFO
- What can go wrong
- An incorrect covenant certificate sent to a lender.
- Forcing function
- A lender query or an audit finding.
Expected-credit-loss provisioning
- Usual owner
- Finance and risk
- What can go wrong
- Misstated profit and capital from staging, loss-rate or overlay errors.
- Forcing function
- An auditor management letter or a regulator inspection observation.
Co-lending and partnership-book reconciliation
- Usual owner
- Finance and operations
- What can go wrong
- The wrong split of collections, interest or fees between partners.
- Forcing function
- New co-lending requirements or a partner dispute.
Risk-based pricing grids
- Usual owner
- Credit and risk
- What can go wrong
- Borrowers charged a rate the policy does not support.
- Forcing function
- A model-governance review or pre-listing scrutiny.
Field and branch incentive computation
- Usual owner
- HR and operations
- What can go wrong
- Staff paid incorrectly, followed by disputes and recoveries.
- Forcing function
- An incident of wrong payouts.
Manufacturing
Inventory provisions
- Usual owner
- Plant finance
- What can go wrong
- Overstated inventory and profit from slow-moving stock, scrap or rejections.
- Forcing function
- A physical-verification gap or a restatement.
Dealer schemes, rebates and sales commission
- Usual owner
- Sales operations and finance
- What can go wrong
- Overpaid schemes and dealer disputes.
- Forcing function
- A wrong payout found, or an audit finding.
Product pricing and quotation costing
- Usual owner
- Sales and costing
- What can go wrong
- A wrong price quoted or published.
- Forcing function
- A margin leak or a wrong-price incident.
Project cost-to-complete and revenue recognition
- Usual owner
- Project finance
- What can go wrong
- Revenue recognised in the wrong period.
- Forcing function
- An auditor revenue-recognition observation.
Related-party transaction limits and approvals
- Usual owner
- Company secretary and finance
- What can go wrong
- Transactions beyond approved limits.
- Forcing function
- Listing-rule compliance or an audit committee query.
Discovery qualification
First decide whether controlled conversion is justified.
The discovery step is a qualification exercise, not an assumption that every important spreadsheet should become a separate application.
Build-readyBuild-ready with conditionsRedesign firstERP is the better routeNo action justified
- 01
The calculation recurs and its output has a material operational, financial or control consequence.
- 02
The logic is sufficiently stable to specify, even if some judgement remains human-owned.
- 03
Historical periods and source files exist so equivalence can be tested rather than assumed.
- 04
There is an accountable owner who can sign the specification and reconciled differences.
- 05
A controlled application is preferable to leaving the logic in the workbook or rebuilding it inside the ERP.
Current delivery boundary
Hosting: client-owned or client-approved environment. CAI does not host client data by default.
Client data: financial data remains in the approved environment and does not enter an AI tool.
Source systems: the ERP remains the source of transactions; write-back is separately scoped.
Ingestion: the standard path starts with report files the existing systems already produce.
Evidence and handover
A client-owned operating handover.
The output is not only a working application. It includes the evidence required to understand what was specified, what was proven and how the process should be operated.
- 01Discovery verdict
Build-ready, build-ready with conditions, redesign first, ERP is the better route, or no action justified.
- 02Signed specification
Every rule and convention in plain language, owned by the client.
- 03Controlled application
Deployed behind approved sign-in, in the agreed environment, with source code.
- 04Replay report and test suite
Proof for every period tested, plus tests that can rerun when a rule changes.
- 05Evidence pack
A traceable record of the source data, rule version, approvals and resulting number.
- 06Runbook and support
How to operate, change a rule, manage access and restore the application.
Start with one critical workbook
Determine whether the process is a good candidate before deciding to build.
Bring the workbook, the accountable owner and a small set of historical periods. The first step is qualification and equivalence design.