The statistical basis for Mark Steyn’s amusing book, America Alone, and for several articles he has written about the coming "caliphate" in "Eurabia", is not entirely clear. The claim, in Steyn’s own words, is that
by some projections, the EU’s population will be 40 percent Muslim by 2025.
Steyn wrote that in February 2005, just after the admission into the EU of 74 million new people from Eastern Europe, almost all of whom are non-Muslim. This blogger has tried to figure out what the source is. After some exhaustive googling, he comes up with the following possible source:
There was an NIC report released in December 2004, a month before the article was written, where four ‘fictional scenarios’ were considered; one of them, starting on page 83, is ‘A New Caliphate’ in which the moslem population of Europe is projected to go as high as between 22 and 37 million; that is not the same thing, of course, as heading towards 40 percent. Could he have made that mistake?
There is a Scotsman article at about the same time that talks of a CIA report (that clearly seems to refer to the NIC2020 project from which the fictional scenario I mentioned was taken) where it is projected that the moslem population will climb from 22 to 37 percent instead of the 22-37 million in the report. So it seems that the Scotsman author, at least, did make the mistake of switching percent in for millions. The only collapse hypothesised within 15 years, in the NIC report, though, is that of US-EU relations, not of the EU itself (as correctly reported by the Scotsman article).
So did Steyn confuse "million" for "percent"? D’oh! Or is Steyn referring to another source? It is the premise of the entire book, after all.