Perhaps you can clarify something for me, because I think I'm missing it.

> Norwegian PNs have your birth date (in DDMMYY format) as the first six digits

So presumably the format is DDMMYYXXXXX (for some arbitrary number of X's), where the XXX represents e.g. an automatically incrementing number of some kind?

Which means that if it's DDMMYYXXX then you can only have 1000 people born on DDMMYY, and if it's DDMMYYXXXXX then you can have 100,000 people born on DDMMYY.

So in order for there to be so many such entries in common that people are denied use of their actual birthday, then one of the following must be true:

1. The XXX counter must be extremely small, in order for it to run out as a result of people 'using up' those Jan 1 dates each year

2. The number of people born on Jan 1 or immigrating to Norway without knowledge of their birthday must be colossal

If it was just DDMMXXXXX (no year) then I can see how this system would fall apart rapidly, but when you're dealing with specifically "people born on Jan 1 2014 or who immigrated to Norway and didn't know their birthday and were born on/around 2014 so that was the year chosen" I'm not sure how that becomes a sufficiently large number to cause these issues. Perhaps this only occurs in specific years where huge numbers of poorly-documented refugees are accepted?

(Happy to be educated, as I must be missing something here)