Isn't it sort of taboo here too, though? I've seen people being told to fuck off for asking that question, or at least politely declined. Even my close family have always been reluctant to divulge their exact income to me, with a few exceptions. It's not a thing that I would ask someone without feeling pretty certain they wouldn't mind.
Yes, you can even order complete records over your region where you see everyone's income tax as well as their capital gains tax in Sweden.
As far as I know, there's no completely open lookup service on the Internet - all of them are pay-walled. None the less, they're public.
I'm fairly confident that this is common amongst the Nordic countries - albeit not looking exactly the same, they share the same spirit of openness.
That said, in Sweden (Which is the only one I have anecdata from) - it's still frowned upon to ask someone what they earn. Talking about what you earn or how much of a raise you got is also socially awkward.
I don't feel talking about what kind of benefits/subsidy is as socially awkward. I'd say it's more accepted.
Something that is completely socially accepted and frequent each year is talking about how large of a tax return you got.
It's the same for Norway, all information is public. It does lead to salaries reaching some sort of equilibrium for the the same role, as it is much harder to argue against an employee, when he points out all his peers are making more money for the same work.
No. Tax information is public in anonymized form. That is different from wages, and the effect is absolutely not the same as if you knew exactly what your peers are making.
I'm trying to encourage talking wages at work, and have gotten my division to disclose theirs, but there's a lot of "oh, but it could lead to discontentment" in the rest of the company. And if you know Norwegians, being mildly at unease is the worst thing that can happen.