The Average Is Not the Operating Condition

An average can be correct and still be the wrong basis for a decision.

A blended labor rate tells you something about the period being measured. It may tell you little about the crew required for a particular product, pack format, or shift.

The question is not whether averages are useful. It is whether the average preserves the differences that matter to the decision.

Segment where the work changes

Begin with the operating conditions that plausibly change the work: product family, manual touches, run length, pack format, changeover requirements, or equipment configuration.

Do not create a category for every possible difference. Choose distinctions the operating team can explain and that the records can support.

Then compare performance within those conditions. If one product requires additional handling, its labor requirement should not disappear inside a blended rate.

If the difference is not supported by the data, keep it as a hypothesis rather than making the segmentation look more certain than it is.

Keep the denominator honest

For a labor-productivity measure, define which paid hours are included and what counts as good output. State how setup, sanitation, rework, and shared support are treated.

Use a representative period. A single visit or unusually easy production week can misstate the normal operating requirement. Conversely, one disrupted week should not automatically become the permanent staffing standard.

The appropriate period depends on the production cycle and the decision. More history is not always better if the process has changed.

Separate performance from mix

A blended rate can improve because the operation ran more easy products, even when no individual process improved. It can worsen for the opposite reason.

Compare like conditions before attributing a change to an improvement project. Show the mix effect separately when it matters.

This protects both sides of the discussion. It prevents an unwarranted success claim and avoids penalizing an operating team for a harder schedule.

Make the analysis change a decision

Choose one staffing or process decision currently based on an average. Identify the operating condition most likely to invalidate it.

Check that condition first. If the result would change the decision, deepen the analysis. If not, avoid building detail that adds no practical value.

The goal is a baseline precise enough to support the decision, not a perfect description of everything the plant does.