I think Rob who is one my readers hit the nail on the head when he in a recent comment commented that one of the things that is clearly differentiating Market Monetarism from other schools is our view of the monetary transmission mechanism. In my reply to his comment I promised Rob to write more on the MM view of the monetary transmission mechanism. I hope this post will do exactly that.

It is well known that Market Monetarists see a significantly less central role for interest rates in the monetary transmission mechanism than New Keynesians (and traditional Keynesians) and Austrians. As traditional monetarists we believe that monetary policy works through numerous channels and that the interest rate channel is just one such channel (See here for a overview of some of these channels here).

A channel by which monetary policy also works is the exchange rate channel. It is well recognised by most economists that a weakening of a country’s currency can boost the country’s nominal GDP (NGDP) – even though most economists would focus on real GDP and inflation rather than at NGDP. However, in my view the general perception about how a weakening the currency impacts the economy is often extremely simplified.

The “normal” story about the exchange rate-transmission mechanism is that a weakening of the currency will lead to an improvement of the country’s competitiveness (as it – rightly – is assumed that prices and wages are sticky) and that will lead to an increase in exports and a decrease in imports and hence increase net exports and in traditional keynesian fashion this will in real GDP (and NGDP). I do not disagree that this is one way that an exchange rate depreciation (or devaluation) can impact RGDP and NGDP. However, in my view the competitiveness channel is far from the most important channel.

I would point to two key effects of a devaluation of a currency. One channel impacts the money supply (M) and the other the velocity of money (V). As we know MV=PY=NGDP this should also make it clear that exchange rates changes can impact NGDP via M or V.

Lets start out in a economy where NGDP is depressed and expectations about the future growth of NGDP is subdued. This could be Japan in the late 1990s or Argentina in 2001 – or Greece today for that matter.

If the central bank today announces that it has devalued the country’s currency by 50% then that would have numerous impacts on expectations. First of all, inflation expectations would increase dramatically (if the announcement is unexpected) as higher import prices likely will be push up inflation, but also because – and more important – the expectation to the future path of NGDP would change and the expectations for money supply growth would change. Take Argentina in 2001. In 2001 the Argentinian central bank was dramatically tightening monetary conditions to maintain the pegged peso rate against the US dollar. This send a clear signal that the authorities was willing to accept a collapse in NGDP to maintain the currency board. Naturally that lead consumers and investors to expect a further collapse in NGDP – expectations basically became deflationary.  However, once the the peg was given up inflation and NGDP expectations spiked. With the peso collapsing the demand for (peso) cash dropped dramatically – hence money demand dropped, which of course in the equation of exchange is the same as an increase in money-velocity. With V spiking and assuming (to begin with) that  the money supply is unchanged NGDP should by definition increase as much as the increase in V. This is the velocity-effect of a devaluation. In the case of Argentina it should of course be noted that the devaluation was not unexpected so velocity started to increase prior to the devaluation and the expectations of a devaluation grew.

Second, in the case of Argentina where the authorities basically “outsourced” the money policy to the Federal Reserve by pegging the peso the dollar. Hence, the Argentine central bank could not independently increase the money supply without giving up the peg. In fact in 2001 there was a massive currency outflow, which naturally lead to a sharp drop in the Argentine FX reserve. In a fixed exchange rate regime it follows that any drop in the foreign currency reserve must lead to an equal drop in the money base. This is exactly what happened in Argentina. However, once the peg was given up the central bank was free to increase the money base. With M increasing (and V increasing as argued above) NGDP would increase further. This is the money supply-effect of a devaluation.

The very strong correlation between Argentine M2 and NGDP can be seen in the graph below (log-scale Index).

I believe that the combined impact of velocity and money supply effects empirically are much stronger than the competitiveness effect devaluation – especially for countries in a deflationary or quasi-deflationary situation like Argentina was in in 2001. This is also strongly confirmed by what happened in Argentina from 2002 and until 2005-7.

This is from Mark Weisbrot’s and Luis Sandoval’s 2007-paper on “Argentina’s economic recovery”:

“However, relatively little of Argentina’s growth over the last five years (2002-2007) is a result of exports or of the favorable prices of Argentina’s exports on world markets. This must be emphasized because the contrary is widely believed, and this mistaken assumption has often been used to dismiss the success or importance of the recovery, or to cast it as an unsustainable “commodity export boom…

During this period (The first six months following the devaluation in 2002) exports grew at a 6.7 percent annual rate and accounted for 71.3 percent of GDP growth. Imports dropped by more than 28 percent and therefore accounted for 167.8 percent of GDP growth during this period. Thus net exports (exports minus imports) accounted for 239.1 percent of GDP growth during the first six months of the recovery. This was countered mainly by declining consumption, with private consumption falling at a 5.0 percent annual rate.

But exports did not play a major role in the rest of the recovery after the first six months. The next phase of the recovery, from the third quarter of 2002 to the second quarter of 2004, was driven by private consumption and investment, with investment growing at a 41.1 percent annual rate during this period. Growth during the third phase of the recovery – the three years ending with the second half of this year – was also driven mainly by private consumption and investment… However, in this phase exports did contribute more than in the previous period, accounting for about 16.2 percent of growth; although imports grew faster, resulting in a negative contribution for net exports. Over the entire recovery through the first half of this year, exports accounted for about 13.6 percent of economic growth, and net exports (exports minus imports) contributed a negative 10.9 percent.

The economy reached its pre-recession level of real GDP in the first quarter of 2005. As of the second quarter this year, GDP was 20.8 percent higher than this previous peak. Since the beginning of the recovery, real (inflation-adjusted) GDP has grown by 50.9 percent, averaging 8.2 percent annually. All this is worth noting partly because Argentina’s rapid expansion is still sometimes dismissed as little more than a rebound from a deep recession.

…the fastest growing sectors of the economy were construction, which increased by 162.7 percent during the recovery; transport, storage and communications (73.4 percent); manufacturing (64.4 percent); and wholesale and retail trade and repair services (62.7 percent).

The impact of this rapid and sustained growth can be seen in the labor market and in household poverty rates… Unemployment fell from 21.5 percent in the first half of 2002 to 9.6 percent for the first half of 2007. The employment-to-population ratio rose from 32.8 percent to 43.4 percent during the same period. And the household poverty rate fell from 41.4 percent in the first half of 2002 to 16.3 percent in the first half of 2007. These are very large changes in unemployment, employment, and poverty rates.”

Hence, the Argentine example clearly confirms the significant importance of monetary effects in the transmission of a devaluation to NGDP (and RGDP for that matter) and at the same time shows that the competitiveness effect is rather unimportant in the big picture.

There are other example out there (there are in fact many…). The US recovery after Roosevelt went of the gold standard in 1933 is exactly the same story. It was not an explosion in exports that sparked the sharp recovery in the US economy in the summer of 1933, but rather the massive monetary easing that resulted from the increase in M and V. This lesson obviously is important when we today are debate whether for example Greece would benefit from leaving the euro area or whether one or another country should maintain a pegged exchange rate regime.

A bit on Danish 1970s FX policy

In my home country of Denmark it is often noted that the numerous devaluations of the Danish krone in the 1970s completely failed to do anything good for the Danish economy and that that proves that devaluations are bad under all circumstances. The Danish example, however, exactly illustrate the problem with the “traditional” perspective on devaluations. Had Danish policy makers instead had an monetary approach to exchange rate policy in 1970s then the policies that would have been implemented would have been completely different.

Denmark – as many other European countries – was struggling with stagflation in the 1970s – both inflation and unemployment was high. Any monetarist would tell you (as Friedman did) that this was a result of a negative supply shock (and general structural problems) combined with overly loose monetary policy. The Danish government by devaluating the krone (again and again…) tried to improve competitiveness and thereby bring down unemployment. However, the high level of unemployment was not due to lack of demand, but rather due to supply side problems. The Danish economy was not in a deflationary trap, but rather in a stagflationary trap. That is the reason the devaluations did not “work” – well it worked perfectly well in terms of increasing inflation, but it did not bring down unemployment as the problem was not lack of demand (contrary to what is the case most places in Europea and the US today).

Conclusion – it’s not about competitiveness

So to conclude, the most important channels of exchange rate policy is monetary – the velocity effect and the money supply – the competitiveness effect is nearly as irrelevant as interest rates is. Countries that suffer from too tight monetary policy can ease monetary policy by announcing a credible devaluation or by letting the currency float. Argentina is a clear example of that. Countries that suffer from supply side problems – like Denmark in 1970s – can not solve the fundamental problems by devaluation.

PS the discussion above is not an endorsement of general economic policy in Argentina after 2001, but only meant as an illustration of the exchange rate channel for monetary policy. Neither is it an recommendation concerning what country XYZ should should do in terms of monetary and exchange rate policy today.

PPS Obviously Scott would remind us that the above discussion is just a variation of what Lars E. O. Svensson is telling us about the fool proof way out of a liquidity trap…

Update – some related posts:

The Chuck Norris effect, Swiss lessons and a (not so) crazy idea
Repeating a (not so) crazy idea – or if Chuck Norris was ECB chief
Argentine lessons for Greece