A Greek hacker stole the personal data of about 9,000,000 Greek residents, which is approximately the same as the population of Greece itself. As Kevin at Lowering the Bar points out, this means that "If You're Greek, Someone Probably Just Stole Your Identity."
Third, according to some reports, the files "appeared to include duplicate entries," so the actual number of affected Greeks may be lower than 9 million, but we don't know how much lower yet. For now we have to assume the number is 9 million, so your answer should have been that there is approximately a 91% chance that any particular Greek citizen's identity has been stolen. That number is high enough that it seems reasonable to say that somebody just stole an entire country's identity, and to use italics to do it.
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.