Tag: price elasticity of demand for exports

Senior Bank of England officials appeared before the House of Commons’ Treasury Select Committee on 21 February to report on the state of the economy and the future path for inflation and interest rates. One topic considered was the role of depreciation.

The pound has depreciated since the referendum on EU membership in June 2016. The exchange rate index today is some 9% below that before the referendum and 15% below the peak a year before the referendum.

It had fallen as much as 14% by October 2016 below the level before the referendum and 20% below its peak, pushed down partly by the cut in Bank Rate from 0.5% to 0.25% following the referendum. In November 2017, the Bank’s Monetary Policy Committee raised Bank Rate back to 0.5%. Two or three more rises of 25 basis points are expected over the next couple of years. This has helped to strengthen sterling somewhat. (Click here for a PowerPoint of the chart below.)

But has the depreciation been advantageous or disadvantageous to the economy? Here the Governor (Mark Carney) and the Chief Economist (Andy Haldane) appeared to differ. Andy Haldane said:

A combination of the weaker pound and a stronger global economy has worked its magic. That has meant that net trade has been a significant contributor, and we expect those effects to continue over the next two or three years. … Depreciations work, and that’s how they work.

By contrast, Mark Carney said:

Depreciations don’t work. They have an economic effect, but they’re not a good economic strategy. They may be an outcome of various things … but it’s how you make yourself poorer.

Are these statements contradictory or are they simply emphasising different effects of depreciation?

Both Andy Haldane and Mark Carney would accept that a depreciation makes imports more expensive and thus reduces real incomes (at least in the short run). They would also accept that a depreciation makes exports priced in pounds cheaper in foreign currency terms and thus can boost the demand for exports.

There is disagreement over two things, however. The first is the effect on people’s real incomes in the long run. Will any fall in real incomes from higher-priced imports in the short run be offset in the long run by higher economic growth?

This relates to a second area of disagreement. This is whether a depreciation can act as a significant driver for exports over the longer term. The increased incentive on the demand side (from consumers abroad to buy UK exports) could be offset by a disincentive for exporters to become more efficient and/or to compete in terms of quality. In other words, although it can give exporters a price advantage, the crucial question is the extent to which they take advantage of this, or merely take higher profits.

The disagreements thus relate primarily to the incentive effects over the longer term.


Bank of England governor says Brexit has made us poorer – as it happened The Guardian, Graeme Wearden (21/2/18)
Brexit will knock 5% off wage growth, says Mark Carney The Guardian, Phillip Inman (21/2/18)


Treasury Committee: Wednesday 21 February 2018 Parliamentlive.tv (21/2/18) (see from 16:08:00)

Bank of England documents

Treasury Select Committee hearing on the February 2018 Inflation Report Bank of England (21/2/18)
Inflation Report – February 2018 Bank of England (8/2/18)


Interest & exchange rates data Bank of England


  1. How does a depreciation affect the demand for and supply of imports and exports?
  2. What determines the size of the effect on inflation of a depreciation?
  3. What is the significance of the price elasticity of demand for and supply of sterling in determining the size of depreciation resulting from a change in confidence or a change in interest rates?
  4. How does productivity growth impact on the effectiveness of a depreciation in leading to higher economic growth?
  5. In what ways might a depreciation affect productivity growth?

The new Japanese government under Shinzo Abe, which took office on 26 December 2012, has been pursuing a policy of weakening the yen. Using a combination of low interest rates, quantitative easing, expansionary fiscal policy and a declared aim of depreciation, the government has succeeded in driving down the value of the yen.

Since mid-November last year, the yen has depreciated by 28% against the dollar, 30% against the euro and 21% against sterling. The effective exchange rate index has fallen by 22% (see first diagram below: click here for a PowerPoint of the diagram).

But will this depreciation succeed in stimulating the Japanese economy and will it improve the balance of trade? The hope is that the falling yen will boost export sales by making them cheaper abroad, and will reduce the demand for imports by making them more expensive in Japan. The balance of trade will thereby improve and higher exports (an injection) and lower imports (a withdrawal) will stimulate aggregate demand and economic growth.

Traditionally Japan has run balance of trade surpluses, but since July 2012, it has been running monthly deficits – the longest run of deficits since 1980. But depreciation cannot be expected to turn this position around immediately. Indeed, theory suggests that the balance of trade is likely to deteriorate before it improves. This is known as the J-curve effect and is illustrated in the second diagram below. As page 768 of Economics, 8th edition states:

At first a devaluation or depreciation might make a current account deficit worse: the J-curve effect. The price elasticities of demand for imports and exports may be low in the short run (see Case Study 25.1 in MyEconLab). Directly after devaluation or depreciation, few extra exports may be sold, and more will have to be paid for imports that do not have immediate substitutes. There is thus an initial deterioration in the balance of trade before it eventually improves. In Figure 25.12 [the second diagram], devaluation takes place at time t1. As you can see, the diagram has a J shape.

Evidence suggests that the first part of the ‘J’ has been experienced in Japan: Japan’s balance of trade has deteriorated. But there is debate over whether the balance of trade will now start to improve. As the article by James Saft states:

But a look at the actual data shows Japanese companies, like British ones during a similar bout of currency weakness in 2008, appear to be more eager to use a newly competitive currency to pad profits through higher margins rather than higher export volumes. Thus far, Japanese exporters appear to be doing just that. Despite yen falls the price of Japanese exports in local currency has barely budged.

“Japanese companies have not actually cut the foreign currency prices of their exports. Just as with the UK exporters, the Japanese have chosen to hold foreign prices constant, maintain market share, and increase the yen value and thus the yen profit associated with yen depreciation,” UBS economist Paul Donovan writes in a note to clients.

The extra profits earned by Japanese companies from export sales may be stockpiled or paid out in dividends rather than reinvested. And what investment does take place may be abroad rather than in Japan. The net effect may be very little stimulus to the Japanese economy.

As stated by Saft above, the UK had a similar experience in the period 2007–9, when sterling depreciated some 27% (see the second diagram). The balance of trade improved very little and UK companies generally priced goods to markets abroad rather than cutting overseas prices.

But times were different then. The world was plunging into recession. Now global markets are mildly growing or static. Nevertheless, there is a danger that the upward slope of the J-curve in Japan may be pretty flat.

Weak yen a boon for investors, not Japan Reuters, James Saft (14/5/13)
Japan’s Trade Data Suggest Even Lower Yen Needed Wall Street Journal, Nick Hastings (22/5/13)
2 Misunderstandings About Japanese Trade Seeking Alpha, Marc Chandler (22/5/13)
Japanese trade deficit widens Financial Times, Ben McLannahan (22/5/13)

BIS effective exchange rate indices Bank for International Settlements
Japan’s balance of trade Trading Economics
UK Trade, March 2013 ONS


  1. Explain the J-curve effect.
  2. Why is there some doubt about whether the Japanese balance of trade will improve significantly?
  3. What will be the consequences for Japanese growth?
  4. If foreign currency prices of Japanese exports do not change, what will determine the amount that Japan exports?
  5. What other measures is the Japanese government taking to stimulate the economy? What will determine the size of the multiplier effects of these measures?
  6. Using data from the ONS plot the UK’s quarterly balance of trade figures from 2007 to the present day. Explain the pattern that emerges.