In fact, I'm not sure that the original suggestion was that it was necessarily the "division sum" which was wrong - merely that 230V, 0.16 and 2,500A do not 'work together' ... which, as you say, means that the 0.16 and/or 2,500A figures must be 'wrong' (and remembering that, at l;east in theory, either of both of those recorded figures could have been ascertained 'by enquiry').
Kind Regards, John
If its one thing i've learnt by spending time reading the posts on this forum it's that whilst on the face of it domestic electrics are quite straight forward, the reality is that it's anything but - when you start digging into things, the rabbit hole goes deep - hence the 'am i missing something' Which EFLImpudence points out:
You are probably correct but who knows which is the wrong figure?
The PFC is the greater of PSCC and PEFC so it could be correct but as the installation is recorded as TN-C-S this is unlikely.
I'm still getting my head arround the implications of TN-S vs TN-C-S, PSSC vs PEFC etc. need to do some more reading / learning. Which is never a bad thing.