Here's an (old) discussion of some of the major points in understanding that question: http://www.forbes.com/sites/timworstall/2012/11/01/so-how-mu...

I haven't seen an explanation of where that 0.005% number comes from, but I would be unsurprised to find similar forms of confusion in it.

The EC's press release is pretty clear on where the number comes from, and I do not see any such forms of confusion there: http://europa.eu/rapid/press-release_IP-16-2923_en.htm

Ah, I see. So what they're saying in this case is that 0.005% is the fraction of Apple's global non-US profits that was paid as tax in Ireland.

That's not the same thing as saying it was "a 0.005% tax rate". The issue is over what fraction of the non-US profits are taxable in Ireland, not over the tax rate.

Whoa, I don't think they're saying that. "Apple Sales International" is not all non-US profits. It's a company buying Apple products from contract manufacturers in other regions and selling them in Europe. It would not be recording any revenue from sales in other regions.

The profits would then be the difference between the cost they bought those products for (+ things like the very substantial payments to Apple US for R&D), vs what they sold those products for.