OEE (overall equipment effectiveness)
OEE tells you how much of the time scheduled for production turned into good parts. It is calculated as the product of three components: availability, performance and quality.
Availability is the time a machine actually ran divided by the time scheduled for it; breakdowns, changeovers, missing material and waiting for an operator eat into it. Performance compares the number of parts produced with the number possible in that time at the reference cycle time. Quality is the share of good parts in everything produced, counting rework against you.
The headline figure is for watching a trend; decisions are made on the components. The same result at two cells may mean breakdowns on an old press or a run of short batches with long changeovers, and those are two different jobs: one for maintenance, one for the order of jobs in the schedule.
Comparing OEE between plants only means something when both sides calculate it the same way. Every company draws the line differently on what counts as scheduled time (breaks, lack of orders, planned maintenance) and on which cycle time is treated as the reference. A figure taken out of that context, your own or somebody else's, says nothing about the state of production.
The signal worth acting on is OEE calculated in the morning from paper notes for the previous shift. An indicator computed late describes the past; to change decisions it has to be built from data coming off the machines as they run.