Reporting, Analytics, and Continuous Improvement
What the exam tests
This domain tests KPI definition and use: OEE, first-pass yield, scrap, cycle time, throughput, downtime Pareto, dashboards, data lineage, and improvement methods such as DMAIC.
Core rules
- Define KPIs with numerator, denominator, time window, and scope. ISO 22400 provides standardized manufacturing KPI concepts; local definitions can differ, so state them.
- First-pass yield counts units that pass without rework or retest divided by units started or completed in the period.
- Pareto analysis ranks loss categories; the largest categories are candidates for action, not automatic proof of root cause.
- Dashboards need consistent master data and time alignment. A beautiful chart built on mixed units or duplicated events is misleading.
- DMAIC structures improvement: define, measure, analyze, improve, control. Control matters because gains erode without monitoring.
Worked example
Downtime categories are 120, 60, 30, and 20 minutes, totaling 230. The top two categories account for 180/230 = 78.3% of downtime. A Pareto focus on those two is reasonable, but the team must still investigate causes. If the 120-minute category is planned changeover and the 60-minute category is a true failure, combining them hides different improvement levers. Reasoning: ranking shows where to look; stratification shows what to fix.
Traps
- Averaging ratios across lines without weighting by volume.
- Comparing OEE across plants with different planned-time definitions.
- Treating correlation in a dashboard as root cause.
- Reporting scrap without identifying whether it is internal, supplier, or customer-return scrap.