The short answer
When ROAS changes suddenly, first check whether the measurement changed. A tracking audit follows a small set of known transactions from business records into the conversion report, then checks whether the spend denominator covers the same scope. It helps separate a data issue from a possible performance change.
Write down the reporting contract
Record the conversion event, eligible order status, revenue components, currency, date basis, attribution window, and campaign scope. Also record whether the report uses click dates, purchase dates, or an acquisition cohort. Without those definitions, two correct reports can still appear inconsistent.
Trace known transactions
Select permitted test orders or existing orders you are authorized to inspect. Compare order identifiers, values, currency codes, and timestamps with conversion records. Check that one purchase does not fire repeatedly after a page refresh and that a failed or canceled payment does not remain counted as completed revenue.
Include a discounted order, a partial refund, and an order with shipping or tax if those cases exist in your business. Follow actual records; do not create artificial customer data in a production report just to complete the checklist.
Reconcile a small batch
Illustrative audit: five eligible orders worth $100 each should contribute $500 under your chosen revenue definition. If the export shows $600 because one order was recorded twice, the extra $100 needs investigation. With $200 spend, the reported ratio is 3× while the reconciled ratio is 2.5×. This example isolates duplication; real differences may have several causes.
Inspect the denominator and timing
Check omitted campaigns, account currency, timezone, credits, and the date range of cost exports. Allow for the documented processing time of each system. Preserve raw exports so a later correction can be explained rather than silently replacing the evidence.
Close the audit with a bounded conclusion
State what was tested, which discrepancy was explained, and what remains unresolved. Correct the source workflow and follow the platform's current adjustment process where appropriate. Resume performance diagnosis using a consistent report, rather than interpreting an unexplained tracking spike as a winning campaign.
Trace known eligible transactions
- Gather: Collect the chosen revenue definition, event payload values, order status and spend scope.
- Produce: Record tested cases, discrepancies, corrections and unresolved gaps.
Decision boundary: A successful page visit does not establish that purchase tracking works.
Next reading
Examples are illustrative, not client results or benchmarks. The calculations use the inputs shown; real-world decisions depend on your records and assumptions. Report a correction.