Lots of potential for skewed data here. Just because a dollar bill you spent in one city turns up in another does not mean *you* went there, as stores and banks ship money around in large quantities. Also, the "Where's George" game is voluntary and certainly not played by everyone who handles a particular bill, which might well travel unreported through a dozen states before reaching someone who chooses to report it. An interesting little diversion, but a long way from definitive.