Mehrling: So you didn’t read at that time the classic banking texts, for example, Bagehot’s Lombard Street? Volcker: Well I read some of Bagehot, and I read a lot of Hawtrey. I remember I read a lot of Hawtrey. Mehrling: Currency and Credit? The Art of Central Banking? Volcker: I don’t remember the names of the books, just being in London. In those days I used to read The Economist and the Financial Times, so I kept up with what was going on in the money markets.
Paul Volcker interviewed by Perry Mehrling (April 18, 2000) in Inside the economist’s mind: conversations with eminent economists (2007) edited by Paul A. Samuelson and William A. Barnett.
Federal Reserve chairman Paul Volcker essentially eliminated M1 as a target indicator. His successor, Alan Greenspan, eliminated M2. On the other hand, in the past year or two, Greenspan has said on various occasions that maybe we should reconsider using M2. The trouble is that all these measures of money cannot be relied on because the velocity of money changes. It is quite unstable.
Lawrence Klein, "Keynsianism Again: Interview with Lawrence Klein", Challenge (May-June 2001)