I was told that that was irrelevant since due to some odd incidents of breeding patterns they tried to make the phone book a couple decades back and discoverd that of the millions of people listed, that predominantly the bulk of them only had four different (apocryphal story, let it go.) surnames so the powers that be, just said "fuck it" to save money on ink.
I think it is Denmark who have a large percentage of people sharing only a few surnames. I know one such name is Hansen - which is shared by about 4.3% of teh Danish population.
However the patronymic seems to work well in Iceland, aprtky because of Iceland's small population (about 300,000 people).
The Iceland phone book lists people under their first name, than theire middle name and lastly their patronymic. The phonebook also lists people's occupation to make it easier to determine if you have the right person.