The normal sense used by statistics bureaus and such is pretty narrow and focuses only on the national currency, usually. So in that sense, given that Bitcoins

The normal sense used by statistics bureaus and such is pretty narrow and focuses only on the national currency, usually. So in that sense, given that Bitcoins are not dollars or yen or anything else, then by definition, no. In a more general sense? I don't know. Folks are still debating whether Bitcoin should even be considered a currency. Maybe it's better thought of as an asset like gold, from how people seem to be using it. Except at least you can make computer chips to mine Bitcoin with, out of gold. So maybe it's not even quite like that. Maybe it's something entirely new and our old models don't model it quite right, sort-of-like currency, but not quite. Now, if we do accept that Bitcoin is operating as a currency, then yes, it would be part of a more fuzzily defined notion of total global (or American) money supply, including all national currencies and currency-like instruments in use. But then, taking that very literally, so are cigarettes, given their use in black market commerce in prisons. For both of them it would be hard to measure, but it's definitely a factor in some way. I don't know if it's affecting inflation. I do suspect that the recent rise in price is at least partly driven by people seeking safe harbour from inflation, especially those who do not have an easy mechanism for buying real estate and the other usual hedges against inflation.