One thing that irks me about performance statistics is that trains which are cancelled are not included in the punctuality measures. After all, a cancelled train can't be delayed. It's as if to say that had the train actually run it would have been on time. But it didn't so it wasn't!
That's not accurate:
Trains fail PPM if:
(1) It does not start where it should start;
(2) It does not finish where it should finish;
(3) It doesn't stop at all the stations it should do;
And
(4) It arrives at its terminus 5 minutes (or 10 minutes for Long-Distance) or more late.
As such, cancelled trains fail PPM.
However, as these trains appear to have been P-Coded and are therefore not in the "Plan of the Day", they can't fail PPM in the first place, as, it was not booked to run in the first place.
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There is a performance metric called CaSL, Cancelled and Significantly Late, so it is measured.
The train has to be part of Plan of the Day to be measured under CaSL.