A deviation count is meaningless without assessed trips. Missing records and cancellations change the denominator.
Control card
- Numerator definition
- Denominator definition
- Exclusion reason
- Definition revision
Set the evidence boundary. Changing exclusions can make improvement a calculation effect. Link numerator and denominator to one definition revision.
Record structure
Define conforming, deviating, unevaluable and cancelled trips in formula. Keep a reason code for each exclusion.
Do not drop unevaluable records to improve the KPI. Report completeness with the rate.
