Don't know if some1 posted before.
I checked bout countries with the most metal bands considering their population.

Finland 5mils pop - 2200 bands
Sweden 10mil pop - 2800 bands
Norway 5 mil pop - 1000 bands
Greece 10mil pop - 1100 bands

As you see Finland has 2200 metal bands and they have only 5mil population
then it comes to Sweden which has a bit more than Finland but it has double population.Norway comes third it has 5 mil like Finland but has half of the bands....and then comes Greece :3 (my country) .So i noticed that Greece is the Forth metal country in the world ;D And Finnish ppl are the most metal-ish ;P Am not 100% sure though,if am mistaken tell me :0

Interesting idea, to be sure. However, with the number of cross-band artists (two [in]famous example: Hellhammer, or the rather incestuous LLN) it would be far better to explain this through number of metal artists per country.

Another random though: the power trio in America (that is, a singer/guitarist, a bassist and a drummer) has kinda lent itself to metal bands, often they will have 3 or 4 members (drummer and bassist/singer or guitarist/singer or drummer, bassist, guitarist and singer), whereas many European bands seem to be more likely to have a designated singer, thus a 5 person line-up. That is more anecdotal, but I wouldn't doubt a correlation.

Very interesting idea, nonetheless

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