The dangers of targeting CPI rather than the GDP deflator – the case of the Czech Republic

It is no secret that Market Monetarists favour nominal GDP level targeting over inflation target. We do so for a number of reasons, but an important reason is that we believe that the central bank should not react to supply shocks are thereby distort the relative prices in the economy. However, for now the Market Monetarist quest for NGDP targeting has not yet lead any central bank in the world to officially switching to NGDP targeting. Inflation targeting still remains the preferred operational framework for central banks in the developed world and partly also in Emerging Markets.

However, when we talk about inflation targeting it is not given what inflation we are talking about. Now you are probably thinking “what is he talking about? Inflation is inflation”. No, there are a number of different measure of inflation and dependent on what measures of inflation the central bank is targeting it might get to very different conclusions about whether to tighten or ease monetary policy.

Most inflation targeting central banks tend to target inflation measured with some kind of consumer price index (CPI). The Consumer Price Index is a fixed basket prices of goods and services. Crucially CPI also includes prices of imported goods and services. Therefor a negative supply shock in the form of higher import prices will show up directly in higher CPI-inflation. Furthermore, increases in indirect taxes will also push up CPI.

Hence, try to imagine a small very open economy where most of the production of the country is exported and everything that is consumed domestically is imported. In such a economy the central bank will basically have no direct influence on inflation – or at least if the central bank targets headline CPI inflation then it will basically be targeting prices determined in the outside world (and by indirect taxes) rather than domestically.

Contrary to CPI the GDP deflator is a price index of all goods and services produced within the country. This of course is what the central bank can impact directly. Therefore, it could seem somewhat paradoxically that central banks around the world tend to focus on CPI rather than on the GDP deflator. In fact I would argue that many central bankers are not even aware about what is happening to the GDP deflator.

It is not surprising that many central bankers knowingly or unknowingly are ignorant of the developments in the GDP deflator. After all normally the GDP deflator and CPI tend to move more or less in sync so “normally” there are not major difference between inflation measured with CPI and GDP deflator. However, we are not in “normal times”.

The deflationary Czech economy

A very good example of the difference between CPI and the GDP deflator is the Czech economy. This is clearly illustrated in the graph below.

The Czech central bank (CNB) is targeting 2% inflation. As the graph shows both CPI and the GDP deflator grew close to a 2% growth-path from the early 2000s and until crisis hit in 2008. However, since then the two measures have diverged dramatically from each other. The consumer price index has clearly moved above the 2%-trend – among other things due to increases in indirect taxes. On the other hand the GDP deflator has at best been flat and one can even say that it until recently was trending downwards.

Hence, if you as a Czech central banker focus on inflation measured by CPI then you might be alarmed by the rise in CPI well above the 2%-trend. And this has in fact been the case with the CNB’s board, which has remained concerned about inflationary risks all through this crisis as the CNB officially targets CPI inflation.

However, if you instead look at the GDP deflator you would realise that the CNB has had too tight monetary policy. In fact one can easily argue that CNB’s policies have been deflationary and as such it is no surprise that the Czech economy now shows a growth pattern more Japanese in style than a catching-up economy. In that regard it should be noted that the Czech economy certainly cannot be said to be a very leveraged economy. Rather both the public and private debt in the Czech Republic is quite low. Hence, there is certainly no “balance sheet recession” here (I believe that such thing does not really exists…). The Czech economy is not growing because monetary policy is deflationary. The GDP deflator shows that very clearly. Unfortunately the CNB does not focus on the GDP deflator, but rather on CPI.

A easy fix for the Czech economy would therefore be for the CNB to acknowledge that CPI gives a wrong impression of inflationary/deflationary risks in the economy and that the CNB therefore in the future will target inflation measured from the GDP deflator and that it because it has undershot this measure of inflation in the past couple of years it will bring the GDP deflator back to it’s pre-crisis trend. That would necessitate an increase in level of the GDP deflator of 6-7% from the present level. There after the CNB could return to targeting growth rate in the GDP deflator around 2% trend level. This could in my view easily be implemented by announcing the policy and then start to implement it through a policy of buying of foreign currency. Such a policy would in my view be fully in line with the CNB’s 2% inflation target and would in no way jeopardize the long time nominal stability of the Czech economy. Rather it would be the best insurance against the present environment of stagnation turning into a debt and financial crisis.

Obviously I think it would make more sense to focus on targeting the NGDP level, but if the CNB insists on targeting inflation then it at least should focus on targeting an inflation measure it can influence directly. The CNB cannot influence global commodity prices or indirect taxes, but it can influence the price of domestically produced products so that is what it should be aiming at rather than to focus on CPI. It is time to replace CPI with the GDP deflator in it’s inflation target.

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  1. Shahid Mehmood

     /  May 14, 2012

    Lars! totally agree with you on this one. People, even with a background in Economics, can’t seem to distinguish between a general rise in price level, and what it entails for the economy as a whole. Since this post is about inflation, it reminds me of an episode of Milton’s TV programm ‘Free to Choose'(i beleive that was the name). In one of the episodes, which pertained to inflation, i was struck by one of Milton’s statement, which basically said that inflation pits one group of the society against the other. The reason is simple: many people may be hurt by rising prices, but there are people who benefit from it too. Many people dont seem to get it, and treat everybody with the same scale when it comes to inflation.

    Your post is a timely reminder that, first of all, we need to know what kind of inflation are we talking about? what exactly are the reasons for it? what’s the measurement methodology, and what’s its effect on various groups in the society? Harking everybody with the same stick (CPI) just doesn’t make sense. And this goes on right before our eyes, despite the fact that CPI, as a measure of rising price elevls, has some serious shortcomings. For example, it doesn’t account for qualitative improvements, or bundled goods. Hope that common sense prevails among the populace, and policymakers recognize the distinction between various forms of inflation.

  2. Shahid, thanks for the feed.

    Yes, it is incredible how few economists recognise the difference between different types of inflation. This is especially important in the present situation.

    Furthermore, in the case of Emerging Markets like the difference between different measures of inflation can be enormous. Take an export oriented economy like the Chinese. While consumer price inflation remain fairly elevated export prices are indeed falling. So do we have deflation or inflation in China at the moment?

    In addition it should be noted that Emerging Markets or developing markets where the standard of living is low food prices is likely to dominate the consumer price index. If a central bank in such a country targets CPI inflation it is likely to react to supply shocks like swings in agriculture output. Effectively in such a world the central bank will be battling the climate. Obviously that is not a good policy. Therefore, nominal GDP level targeting makes a lot more sense (also) for Emerging Markets. Alternatively I have recommend a policy of targeting the export price in line with Jeffrey Frankel’s PEP proposal.

  3. I totally agree! CPI is a very bad measure of the purchasing power of a currency, and even worse in a small open economy. GDP delator would be better, and it would reduce the degree of activism of central bankers during business expansions.
    Anyhow, I do not think inflation stabilisation is the best criterion to conduct monetary policy.

  4. Benjamin

     /  May 15, 2012

    Hi Lars,

    Thanks for these posts. I’m just a student and we briefly skimmed over NGDP targeting in my monetary economics class. Could you please explain how the GDP Deflator is measured in practice?

  5. Great post Lars.
    Benjamin, it is basically a by-product of the national accounts process. The statistical authority (in Australia, the ABS) receives money and volume measures which it puts together to form estimates of NGDP and RGDP. The GDP deflator is how the statstical authority moves from monetary to “real” aggregates, using its volume measures to estimate the deflator.

    The wikipedia article is not very helpful on the mechanics, but gives the general idea:

  6. James in London

     /  July 13, 2012

    One thing about Czechs that makes them more relatively more worried about “inflation” than others is that they are a nation of savers, or creditors. If they were a nation with larger external financing of their debts like the US they would be less worried. Inflation is the debtors’ friend.

    • James, I actually think that has very little to do with the actual policies of the Czech central bank. I believe the problem primarily is analytical – the CNB simply thinks that Czech monetary policy is easy because interest rates are low.

  7. Alex

     /  May 24, 2013

    Hi Lars,
    I’m not an economist so I’m a little confused by this argument. Even though foreign goods are produced abroad, they are sold in the domestic currency. If the central bank expands the money supply the exchange rate adjusts to increase the price of imports in terms of the domestic currency. So why can’t central banks control import prices?

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