MES, MOM & Shop-Floor Data Systems worked example

Line Status Accuracy at 99% target accuracy rate: a worked example

What does the result look like when target accuracy rate reaches 99%? The full calculation is worked below with real intermediate numbers. Use when validating MES data quality for OEE reporting. If line status is inaccurate, your availability and OEE numbers will be unreliable. Run spot-check audits and enter results here.

The inputs for this scenario

  • Status checks matching actual state: 87 checks (unchanged)
  • Total status spot-checks performed: 100 checks (unchanged)
  • Target accuracy rate: 99 % (raised for this scenario; the documented default is 95)

Working through the calculation

  • Applying the documented formula (Line status accuracy = (matching checks / total spot-checks) x 100) to the inputs above produces each figure below.
  • At this operating point the engine returns 87 % for line status accuracy rate, the number this scenario is built around.
  • At this operating point the engine returns 12 points for gap to accuracy target.
  • At this operating point the engine returns 87 count for matching status checks.
  • At this operating point the engine returns 100 count for total spot-checks performed.

How this compares with the baseline

  • Against the tool's baseline example, where target accuracy rate sits at 95% and the headline result is 87 %, this scenario lands almost exactly on the baseline at 87 %.
  • A figure at this level is achievable when target accuracy rate is genuinely sustained, not just peaked for a shift. Accuracy depends entirely on a representative, unbiased sample — checking only during steady running overstates accuracy, since most errors occur during fast state transitions like micro-stops.

Results at a glance

  • Line status accuracy rate: 87 % (headline result)
  • Gap to accuracy target: 12 points
  • Matching status checks: 87 count
  • Total spot-checks performed: 100 count

Run it with your numbers

  • Every input above is editable in the live Line Status Accuracy calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.