Operational efficiency index

What it measures

The operational efficiency index measures the balance between the real cost incurred and the expected cost according to the historical pattern. It answers neither "was the employee there?" nor "how many hours did they do?", but whether the operation is moving within a healthy range against its own consolidated behaviour.

To calculate it, the system uses the average effective cost per workday, the consolidated average cost from the history, the consistency of the pattern and the statistical volume available. It requires a minimum data base: without it, the indicator does not make a judgement.

Alongside it, the profile includes the operational inefficiency index, its inverse reading, and the return per hour worked, which relates net hours to the associated cost and the stability of the pattern. This last one describes the structural use of time, not individual productivity: an hour with low return points to a problem of work organisation before one of the person who worked it.

What goes into the calculation

The index rests on four elements, and all four matter:

• The average effective cost per workday for the period analysed.
• The consolidated average cost from the history, which acts as the reference.
• The consistency of the pattern: erratic behaviour lowers the conclusion even if the figures add up.
• The statistical volume available. Without a minimum base of workdays, the indicator does not make a judgement.

That last point is deliberate: the system prefers to say *gathering data* rather than accept a conclusion built on four workdays.

The difference between efficiency and reliability

It is worth not confusing them, because they measure different things:

• Reliability measures the consistency of behaviour: whether the person is where they should be, when they should be.
• Operational efficiency measures the economic balance: whether what it costs to operate corresponds with what it has historically cost.

A site can have high reliability and low efficiency —everyone keeps to their schedule, but the cost per workday has shot up— or the other way round. Reading them together is what gives the full picture.

How to interpret it

The indicator is not published as a mark out of 100 or as a ranking between people. It is read by its deviation from its own history and always accompanied by its maturity state and its confidence level.

Faced with a value that draws attention, the sensible order of questions is:

1. Is there enough data? If the state says *gathering data* or *partial evidence*, there is no conclusion to draw yet.
2. Is the configuration complete? A strange cost per workday usually comes from hourly rates left blank or set incorrectly, not from operations. The dashboard's data status block indicates this.
3. Is it the person or the site? Before attributing a poor indicator to somebody, look at the site effect in the Operations dashboard. It is exactly the question that indicator answers.
4. Is it sustained or one-off? An isolated deviation is not a trend. The indicators are built so as not to penalise occasional flexibility.

Use in performance appraisals

This index describes the structural use of time and the balance of costs, not individual performance. An employee does not "perform less" because their cost per output is high: they may be on a badly sized shift, covering a position with no relief or at a site that wears down those who pass through it.

For formal appraisals, combine this index with reliability and with the operational assessment of the employee: each measures a different aspect and none, in isolation, offers a complete picture. The quality of the work carried out is measured through task validation and rating, not here.