I don't know the answer to your question, but based on the large number of people on this website who were offered the MA but are not accepting the offer, I think they probably offer it to quite a lot of people. Since it isn't funded, probably only a small percentage of people actually do it. I talked to some profs at other programs to which I was accepted, and they all said it would be "tempting" to accept the Columbia MA, even without funding, because of the amazing resources, reputation, and (at least reputation for) rigor. Plus, you would be in NYC, a place where connections and resources abound for almost any field of study. It all depends on what you make of it, not on numbers!