That's nice article. BOE does good research especially Haldane. I used to work with some of his peers.  My own concept of money is a bit broader and includes any representation of value, so equities and commercial credit etc. are included, they are just money with unique properties, but all represent value.  more in my book. www.thenatureofvalue.com  A great site on money which is working putting out M4 aggregate figures is http://www.centerforfinancialstability.org/index.php I was on a panel with the CEO a few weeks back. they have some cool historical data along with compelling new aggregates.