Not sure of the direct answer to your question, but I've noticed on
South Eastern trains that when the train is later than the magical four
minutes, the automated announcements always reflect this. So, for
example, if the 11.25 arrives at 11.28, the announcement will be "The
train at Platform 4 is the 11.25 to...", if it arrives at 11.30 the
announcement will be "The train at Platform 4 is the delayed 11.25
to...".

And who decided that +/- 4 minutes means "on time", anyway? Can't see
the Swiss accepting that...

Patrick

I've always been troubled by the whole %age On Time concept both for
the reason you mention and the concept of using trains rather than
passengers as being On Time.

What I mean to say is that if you take - say - the NLL and look at the
delays. Last year the line reported punctuality of 95 or 96% - assuming
that this was based on the real running times of the trains and based
on my personal experiences, it must have meant that almost all the
off-peak trains were running on time. But these often run 10% full (and
those passengers are less likely to be daily users) while the rush hour
trains are packed.

Therefore, a much larger %age than 4% or 5% were delayed on the line.
This explains the mismatch between what - on the face of it - appears
to be a good figure and the experiences of regular passengers you hear
from, when discussing the line.