Maintenance statistics can provide context, but consistent site level measures are more useful for operational decisions. Market forecasts, international surveys and results from individual businesses are not directly transferable targets.
This revision replaces the earlier collection of dated market figures with ten practical metrics. Define the period, data source, owner and treatment of downtime for each measure.
Ten metrics with explicit definitions
- 1. Unplanned downtime: the sum of stoppages classified as unplanned during the period. Define how overlapping events are handled to avoid double counting.
- 2. Technical availability: agreed required operating time minus included downtime, divided by required operating time. Explain which types of stoppage are included.
- 3. MTBF: observed operating time divided by the number of included failures for repairable equipment. With no failures in the period, there is no observed average between failures to calculate.
- 4. Mean active repair duration: total active repair time divided by the corresponding number of repairs. Record waiting separately. If MTTR is defined differently at your site, state that definition.
- 5. Schedule compliance: due tasks completed by their deadline divided by all tasks due in the period. Later changes to deadlines must remain traceable.
- 6. Repeat failure rate: recurring faults under your defined criteria divided by the relevant failures. Asset, failure mode and observation window must match.
- 7. Planned work share: hours spent on work prepared in advance divided by all recorded maintenance hours. An order created shortly before execution is not necessarily planned work.
- 8. Backlog in weeks: estimated effort for approved outstanding work divided by realistic weekly capacity. Show blocked work separately.
- 9. Waiting for spares: elapsed time from documented material need to availability for the order. Purchasing lead time and internal search time can be examined separately.
- 10. Maintenance cost per unit of activity: defined cost divided by operating hours, good output or another suitable denominator. Keep the cost boundary consistent.
Use a calculation instead of an assumed benchmark
An illustrative asset is required for 400 hours. If 20 hours count as downtime under the selected definition, availability is 95 percent: 380 divided by 400. This is an example, not an industry target or a customer result.
If utilisation changes in the next month, examine absolute downtime and availability together. They may move differently.
Interpret external statistics carefully
Check year, geography, occupation, sample and measurement method. For example, the US Bureau of Labor Statistics reports on a defined US occupation. Its data cannot directly establish staffing needs for a maintenance department in Germany.
Start with a few useful measures
Select metrics with available data and a corresponding decision. Record times, status and asset relationships consistently in the CMMS. Discuss deviations with accountable people and document the action. A dashboard is valuable when it improves decisions, rather than merely displaying more numbers.
