Progress on the Monetary Policy and Banking Debate

We seem to be moving forward with this discussion on monetary policy, banking, and reserves. John Carney does a good job of summarising some of the initial forays in this back and forth. I am going to try my hand at framing the discussion here using my own analysis of the comments iteratively, with the assistance of more comments of course. Where there are mistakes, I will fix them accordingly.

The last post I wrote and a follow on post by Tom Hickey at Mike Norman’s blog get at the heart of the debate and so I will try to characterise what is being said here.


We have been living in a world predominated by floating exchange rates and currency non-convertibility for forty years now. Nevertheless, most of economics world seems to take a fixed exchange rate, Bretton Woods, or gold standard view of money and banking. In that world, as Warren Mosler quipped, bank lending is reserve constrained with the interest rate an endogenous variable via bank competition for reserves.

I put it this way in December [emphasis added]:

In the old gold convertible system, the central bank had to jack up rates to prevent an outflow of gold. Interest rates were the release valve. But in those old days, only by adjusting the gold peg i.e. depreciating the currency, could countries under attack get away with low rates once the vigilantes were on to them. That’s what happened during the Great Depression. Once the conversion was broken, the currency depreciated and depression lessened immediately.

Today the release valve is always the currency because there is no gold tether. So the currency gives way, not interest rates.

Bond vigilantes and the currency relief valve

What this in effect means for the domestic banking system is that in a nonconvertible floating exchange rate system, lending is not reserve constrained as banks can create reserves by making a loan that creates a deposit. Any one institution can always borrow reserves from other banks or from the Fed itself if it finds itself short of reserves (See this BIS paper from 2010 for further discussion).

The US government, as monopoly issuer of its own sovereign currency, has given the Fed monopoly power in the market for base money. The Fed then exercises this monopoly power by targeting the overnight rate for money, the fed funds rate. That is to say, the Fed targets a rate or a price, not a quantity. Almost all modern central banks of today operate with explicit interest rate targets, allowing the overnight rate to fluctuate within a range. Any monopolist can only control either price or quantity, not both. Now, central banks could target something else like reserves to transmit monetary policy into the economy; and they have done in the past. The Fed targeted reserves from 1979-1982. What the Fed found was that it had only a controlling influence on base money because targeting the monetary base meant volatility in interest rates (see this 2004 ECB paper for further discussion). But, more importantly, because bank loans create deposits that actually need reserves to maintain the integrity of the payments system, the Fed is forced to supply them according to its legal mandate.

In short, reserves are about helping set interest rates, not about pyramiding money on a reserve base.

Under present institutional arrangements, the Fed Funds rate is dependent on the Fed’s supplying the required amount of reserves at any given reserve ratio to keep the interest rate at its target or within its target band.  The Fed can’t target a rate unless it supplies banks with all the reserves that the banks need to make loans at that rate. This means that central banks must be committed to supplying as many reserves as banks want/need in accordance with the lending that they do subject to their capital constraints. Failure to supply the reserves means failure to hit the interest rate target. So in practice, if a banking system as a whole is at the reserve limit, central banks always increase the level of reserves desired by the system in order to maintain the interest rate. Not doing so means at once that the Fed cannot hit its target or that transactions fail as the payments system breaks down.

In sum: In a nonconvertible. floating exchange rate system, the amount of credit in the system is determined by the risk-reward calculations of banks in granting loans and the demand for those loans. Banks are not reserve constrained. They are capital constrained. Financial institutions grant credit based on the capital they have to deal with losses associated with that activity.

I don’t think anything I wrote is particularly controversial for those with banking and money as their primary economic discipline or area of study. But if you read textbooks like the one I got in business school by Glenn Hubbard, you find sentences like “The monetary base sometimes is called high-powered money because a given amount of base allows creation of a multiple amount of money” (p. 420, Money, the Financial System and the Economy, Hubbard, 1995). This suggests that the banks in fact are pyramiding credit/money creation on the back of reserves when this is not the case. I checked my intro college economics textbook by Baumol and Blinder from 1985 and it’s exactly the same kind of stuff. The reality is that banks are not reserve-constrained because the Fed must supply reserves to back loans already granted. Only if and when the Fed decides to raise the fed funds rate to curtail credit growth will reserves be constrained. And they will be demand-constrained, not supply-constrained.

Central Bank Flexibility – tactics, strategy, and policy

Given that framing above, the question everyone is asking is whether any of that matters over the long-term. Here’s how I explained Nick Rowe’s objection to the concept of endogenous money:

I think the real difference between what Nick Rowe is saying and what people like Scott Fullwiler and Steve Keen are saying is that Nick believes over the medium-term, central bank interest rate policy is endogenous. What I think Nick means is that Scott Fullwiler’s view is reasonably clear and straightforward in his view that central monetary policy is exogenous but that it only matters over a short-term time horizon because central bank interest rate policy adjusts endogenously over the medium-term to commercial bank and other economic variables such that it is really endogenous rather than exogenous.

Further, I think Nick Rowe is saying that it creates an expectation of central bank interest rate policy merely by announcing its target rate and the market moves to accommodate that target, knowing the central bank is the monopoly supplier of reserves. In that sense the central bank has control. But what he seems to suggest is that the central bank policy rate cannot be determined independent of macroeconomic variables (like inflation specifically) and that central bank may be forced to change policy based on these, making it possible to treat the central bank policy rate as medium-term endogenous.

Nick Rowe says my view of his previous commentary is fairly accurate. Scott Fullwiler doesn’t like the terms short- and medium-term. He would rather see us talk about Fed tactics, strategy and policy.

Scott frames it this way (with minor edits for readability):

  1. Tactics – can the central bank directly target reserve balances, monetary base, etc?
  2. Strategy – what sort of rules/discretion balance does the central bank follow in adjusting the target it has set tactically. How often? How big of an adjustment each time? By what criteria?
  3. Policy – How does the macro economy work and what role can or should the central bank play in stabilizing it?

Scott goes on to say that:

The debate between Krugman/Keen once it got to issues related to the money multiplier and loanable funds was about tactics–can banks individually or collectively create loans without regard to deposits or reserve balances? This is closely linked to an understanding of what banks are/do and hence Krugman’s view that they didn’t need to be included since inserting them didn’t change how one should view the money multiplier or loanable funds models. This is where I jumped in, because Krugman in my view was completely wrong on these points.

But Krugman’s reply to me, and Rowe’s post, brought in strategy and policy–”the central bank must change the interest rate target by adjusting to events and expectations” which is about how the central bank should adjust its target (strategy) within the context of how the macroeconomy works and interacts with monetary policy (policy)…

The MMT view is that we need to understand how the tactics work to inform our strategy and even our understanding of how the economy works. Krugman tried to suggest understanding the tactics is irrelevant to these two. This is a very significant distinction between the approaches.

Further, in MMT, we keep these three (tactics, strategy, policy) separate when we discuss them. Neoclassicals generally don’t–so, when I say the central bank must set an interest rate target (tactics) but can move that target wherever it wants (the possibilities for strategy), Nick says no the cb must set a target that responds to the economy and thus must be endogenous (strategy in the context of view of macroeconomy). We end up talking past each other as I have not invoked yet at all how central banks “should” set strategy with regard to how the macroeconomy works. While we will disagree on the latter, in our view jumping to that without clarifying and setting a common language for tactics and strategy complicates the discussion unnecessarily.

This is progress.

Translation: we agree on the basics here but semantically there are differences.

  • MMT’ers believe the central bank, as monopoly supplier of reserves has monopoly power and therefore full discretion to act as an exogenous actor.
  • Nick Rowe says a central bank must set a target that responds iteratively to the economic variables like inflation and thus must be endogenous as a overarching strategy in the context of a macroeconomy).

I think that’s where we stand.

My Conclusions

  • We have been living in a world of floating exchange rates and currency non-convertibility but the economics world very often – and wrongly – takes a Bretton Woods view of money and banking.
  • The Bretton Woods world is one in which bank lending is reserve constrained with the interest rate an endogenous variable via bank competition for reserves.
  • In a nonconvertible floating exchange rate system, lending is not reserve constrained (over the short-term) as banks can create reserves by making a loan that creates a deposit. Any one institution can always borrow reserves from other banks or from the Fed itself if it finds itself short of reserves. If a banking system as a whole is at the reserve limit, central banks always increase the level of reserves desired by the system in order to maintain the interest rate.
  • But questions remain about what a central bank can target and to what effect and as to the discretion a central bank has in adjusting any target it has set “tactically”. Some say that over the long-term a central bank must respond iteratively to macro economic variables. Others believe the central bank has full discretion to set policy as an exogenous actor.
  • My question is whether the above suggests banks MUST be including in any realistic economic model for it to have predictive power even in more extreme economic circumstances like the ones that existed during the great credit bubble. The Great Financial Crisis would suggest yes. yet, many in the economics field resist this notion. Hopefully, we can get more answers on this question as a result of this post.

This post originally appeared at Credit Writedowns and is posted with permission.