detect phantom stops - when a bus was supposed to arrive at a station but didn't

[OriHoch]

Phantom stop: When a bus is supposed to arrive at the station, but just doesn't. It's not that the bus arrives late or early, it just doesn't show up.

The ETA counter at the station gets to 0 and then back to 30 (whenever the next bus arrives), without any bus being seen.

I'd like to get meaningful statistics on when and where such a phantom stop occurs, potentially aggregating the info (e.g. Line 61 at bus stop 21614 had 21% phantom stops on 2022-03-14)