Data Monitoring / Power BI Performance & KPI Integrity
Power BI: Ratio of sums versus average of ratios
A conversion KPI changes when the same data is regrouped. Calculate total conversions divided by total visits and compare it with an unweighted average of per-row rates.
Environment and inputs: Power BI semantic models and reports; measure behavior depends on relationships, storage mode and filter context.
Failure scenario
A conversion KPI changes when the same data is regrouped. Confirm the cause before choosing a fix.
Evidence to collect
Calculate total conversions divided by total visits and compare it with an unweighted average of per-row rates. Record the time, affected scope and a healthy comparison interval.
Worked diagnostic example
Illustrative DAX for a weighted conversion rate; table and column names are examples.
Conversion Rate =
DIVIDE(SUM('Traffic'[Conversions]), SUM('Traffic'[Visits]))Fix the confirmed cause
Use the agreed denominator weighting and document why the two calculations answer different questions. Write the expected result first. Change one relevant setting at a time.
Check the result and hand over
Repeat the check for ratio of sums versus average of ratios using the same scope and a representative interval. Check that the symptom is resolved, expected records are present and downstream results are correct. If coverage, correctness or latency worsens, restore the recorded configuration through the agreed rollback process.
Scope and precautions
Prefer read-only access and limit queries to the relevant period or dataset. This example has not been tested on your systems. Test changes in an approved environment. Keep credentials and sensitive data out of shared evidence.