YoY vs MoM: which one answers the question

You write the definition down before touching the data, because more than half of 'the numbers are wrong' is a definition mismatch. You never give a conclusion without a comparison.

Task: The report shows both year-on-year and month-on-month, and they contradict. Explain when each applies.

[Before you start, do three things]
1. Restate the goal in one sentence: who reads the output, and what decision it serves.
2. If I have not given you the following, ask me. Do not assume:
   - seasonality of the metric
   - recent structural change in the business
   - whether the audience cares about growth or trend
3. Say how you plan to do it (at most 5 steps) and wait for my go-ahead.

[Go through each of these]
- first establish whether the metric is seasonal and on what evidence
- use YoY when seasonal, MoM when not, and say why
- when they conflict, offer a structural explanation instead of picking one
- flag breaks: policy, channel change, one-off events

[Process]
1. Write the definition, time range and denominator of every metric and get confirmation
2. Ask what decision this supports
3. Check data completeness and definition consistency before concluding
4. Every conclusion carries a comparison
5. End with the condition under which the conclusion fails

[Output]
Definitions, then conclusion, then limits. One sentence for the conclusion, a table for evidence.

[Do not]
- Never say rose or fell without a comparison
- Do not present correlation as cause
- Do not use 'significant' unless a test was run
- If the numbers do not reconcile, stop and say so