Tag: potential output

On 2 November, the Bank of England raised Bank rate from 0.25% to 0.5% – the first rise since July 2007. But was now the right time to raise interest rates? Seven of the nine-person Monetary Policy Committee voted to do so; two voted to keep Bank Rate at 0.25%.

Raising the rate, on first sight, may seem a surprising decision as growth remains sluggish. Indeed, the two MPC members who voted against the rise argued that wage growth was too weak to justify the rise. Also, inflation is likely to fall as the effects of the Brexit-vote-induced depreciation of sterling on prices feeds through the economy. In other words, prices are likely to settle at the new higher levels but will not carry on rising – at least not at the same rate.

So why did the other seven members vote to raise Bank Rate. There are three main arguments:

Inflation, at 3%, is above the target of 2% and is likely to stay above the target if interest rates are not raised.
There is little spare capacity in the economy, with low unemployment. There is no shortage of aggregate demand relative to output.
With productivity growth being negligible and persistently below that before the financial crisis, aggregate demand, although growing slower than in the past, is growing excessively relative to the growth in aggregate supply.

As the Governor stated at the press conference:

In many respects, the decision today is straightforward: with inflation high, slack disappearing, and the economy growing at rates above its speed limit, inflation is unlikely to return to the 2% target without some increase in interest rates.

But, of course, the MPC’s forecasts may turn out to be incorrect. Many things are hard to predict. These include: the outcomes of the Brexit negotiations; consumer and business confidence and their effects on consumption and investment; levels of growth in other countries and their effects on UK exports; and the effects of the higher interest rates on saving and borrowing and hence on aggregate demand.

The Bank of England is well aware of these uncertainties. Although it plans two more rises in the coming months and then Bank Rate remaining at 1% for some time, this is based on its current assessment of the outlook for the economy. If circumstances change, the Bank will adjust the timing and total amount of future interest rate changes.

There are, however, dangers in the rise in interest rates. Household debt is at very high levels and, although the cost of servicing these debts is relatively low, even a rise in interest rates of just 0.25 percentage points can represent a large percentage increase. For example, a rise in a typical variable mortgage interest rate from 4.25% to 4.5% represents a 5.9% increase. Any resulting decline in consumer spending could dent business confidence and reduce investment.

Nevertheless, the Bank estimates that the effect of higher mortgage rates is likely to be small, given that some 60% of mortgages are at fixed rates. However, people need to refinance such rates every two or three years and may also worry about the rises to come promised by the Bank.


Bank of England deputy says interest rate rise means pain for households and more hikes could be in store Independent, Ben Chapman (3/11/17)
UK interest rates: Bank of England shrugs off Brexit nerves to launch first hike in over a decade Independent, Ben Chu (2/11/17)
Bank of England takes slow lane after first rate hike since Reuters, David Milliken, William Schomberg and Julian Satterthwaite (2/11/17)
First UK rate rise in a decade will be a slow burn Financial Times, Gemma Tetlow (2/11/17)
The Bank of England’s Rate Rise Could Spook Britain’s Economy Bloomberg, Fergal O’Brien and Brian Swint (3/11/17)
Bank of England hikes rates for the first time in a decade CNBC, Sam Meredith (2/11/17)
Interest rates rise in Britain for the first time in a decade The Economist (2/11/17)

Bank of England publications

Bank of England Inflation Report Press Conference, Opening Remarks Financial Times on YouTube, Mark Carney (2/11/17)
Bank of England Inflation Report Press Conference, Opening Remarks Bank of England, Mark Carney (2/11/17)
Inflation Report Press Conference (full) Bank of England on YouTube (2/11/17)
Inflation Report Bank of England (November 2017)
Monetary Policy Summary and minutes of the Monetary Policy Committee meeting ending on 1 November 2017 Bank of England (2/11/17)


  1. Why did the majority of MPC members feel that now was the right time to raise interest rates whereas a month ago was the wrong time?
  2. Why did the exchange rate fall when the announcement was made?
  3. How does a monetary policy of targeting the rate of inflation affect the balance between aggregate demand and aggregate supply?
  4. Can monetary policy affect potential output, or only actual output?
  5. If recent forecasts have downgraded productivity growth and hence long-term economic growth, does this support the argument for raising interest rates or does it suggest that monetary policy should be more expansionary?
  6. Why does the MPC effectively target inflation in the future (typically in 24 months’ time) rather than inflation today? Note that Mark Carney at the press conference said, “… it isn’t so much where inflation is now, but where it’s going that concerns us.”
  7. To what extent can the Bank of England’s monetary policy be described as ‘discretionary’?

The article below looks at the economy of Brazil. The statistics do not look good. Real output fell last year by 3.8% and this year it is expected to fall by another 3.3%. Inflation this year is expected to be 9.0% and unemployment 11.2%, with the government deficit expected to be 10.4% of GDP.

The article considers Keynesian economics in the light of the case of Brazil, which is suffering from declining potential supply, but excess demand. It compares Brazil with the case of most developed countries in the aftermath of the financial crisis. Here countries have suffered from a lack of demand, made worse by austerity policies, and only helped by expansionary monetary policy. But the effect of the monetary policy has generally been weak, as much of the extra money has been used to purchase assets rather than funding a growth in aggregate demand.

Different policy prescriptions are proposed in the article. For developed countries struggling to grow, the solution would seem to be expansionary fiscal policy, made easy to fund by lower interest rates. For Brazil, by contrast, the solution proposed is one of austerity. Fiscal policy should be tightened. As the article states:

Spending restraint might well prove painful for some members of Brazilian society. But hyperinflation and default are hardly a walk in the park for those struggling to get by. Generally speaking, austerity has been a misguided policy approach in recent years. But Brazil is a special case. For now, anyway.

The tight fiscal policies could be accompanied by supply-side policies aimed at reducing bureaucracy and inefficiency.


Brazil and the new old normal: There is more than one kind of economic mess to be in The Economist, Free Exchange Economics (12/10/16)


  1. Explain what is meant by ‘crowding out’.
  2. What is meant by the ‘liquidity trap’? Why are many countries in the developed world currently in a liquidity trap?
  3. Why have central banks in the developed world found it difficult to stimulate growth with policies of quantitative easing?
  4. Under what circumstances would austerity policies be valuable in the developed world?
  5. Why is crowding out of fiscal policy unlikely to occur to any great extent in Europe, but is highly likely to occur in Brazil?
  6. What has happened to potential GDP in Brazil in the past couple of years?
  7. What is meant by the ‘terms of trade’? Why have Brazil’s terms of trade deteriorated?
  8. What sort of policies could the Brazilian government pursue to raise growth rates? Are these demand-side or supply-side policies?
  9. Should Brazil pursue austerity policies and, if so, what form should they take?

The International Monetary Fund has just published its six-monthly World Economic Outlook (WEO). The publication assesses the state of the global economy and forecasts economic growth and other indicators over the next few years. So what is this latest edition predicting?

Well, once again the IMF had to adjust its global economic growth forecasts down from those made six months ago, which in turn were lower than those made a year ago. As Larry Elliott comments in the Guardian article linked below:

Every year, economists at the fund predict that recovery is about to move up a gear, and every year they are disappointed. The IMF has over-estimated global growth by one percentage point a year on average for the past four years.

In this latest edition, the IMF is predicting that growth in 2015 will be slightly higher in developed countries than in 2014 (2.0% compared with 1.8%), but will continue to slow for the fifth year in emerging market and developing countries (4.0% in 2015 compared with 4.6% in 2014 and 7.5% in 2010).

In an environment of declining commodity prices, reduced capital flows to emerging markets and pressure on their currencies, and increasing financial market volatility, downside risks to the outlook have risen, particularly for emerging market and developing economies.

So what is the cause of this sluggish growth in developed countries and lower growth in developing countries? Is lower long-term growth the new norm? Or is this a cyclical effect – albeit protracted – with the world economy set to resume its pre-financial-crisis growth rates eventually?

To achieve faster economic growth in the longer term, potential national output must grow more rapidly. This can be achieved by a combination of more rapid technological progress and higher investment in both physical and human capital. But in the short term, aggregate demand must expand sufficiently rapidly. Higher short-term growth will encourage higher investment, which in turn will encourage faster growth in potential national output.

But aggregate demand remains subdued. Many countries are battling to cut budget deficits, and lending to the private sector is being constrained by banks still seeking to repair their balance sheets. Slowing growth in China and other emerging economies is dampening demand for raw materials and this is impacting on primary exporting countries, which are faced with lower exports and lower commodity prices.

Quantitative easing and rock bottom interest rates have helped somewhat to offset these adverse effects on aggregate demand, but as the USA and UK come closer to raising interest rates, so this could dampen global demand further and cause capital to flow from developing countries to the USA in search of higher interest rates. This will put downward pressure on developing countries’ exchange rates, which, while making their exports more competitive, will make it harder for them to finance dollar-denominated debt.

As we have seen, long-term growth depends on growth in potential output, but productivity growth has been slower since the financial crisis. As the Foreword to the report states:

The ongoing experience of slow productivity growth suggests that long-run potential output growth may have fallen broadly across economies. Persistently low investment helps explain limited labour productivity and wage gains, although the joint productivity of all factors of production, not just labour, has also been slow. Low aggregate demand is one factor that discourages investment, as the last World Economic Outlook report showed. Slow expected potential growth itself dampens aggregate demand, further limiting investment, in a vicious circle.

But is this lower growth in potential output entirely the result of lower demand? And will the effect be permanent? Is it a form of hysteresis, with the effect persisting even when the initial causes have disappeared? Or will advances in technology, especially in the fields of robotics, nanotechnology and bioengineering, allow potential growth to resume once confidence returns?

Which brings us back to the short and medium terms. What can be done by governments to stimulate sustained recovery? The IMF proposes a focus on productive infrastructure investment, which will increase both aggregate demand and aggregate supply, and also structural reforms. At the same time, loose monetary policy should continue for some time – certainly as long as the current era of falling commodity prices, low inflation and sluggish growth in demand persists.


Uncertainty, Complex Forces Weigh on Global Growth IMF Survey Magazine (6/10/15)
A worried IMF is starting to scratch its head The Guardian, Larry Elliott (6/10/15)
Storm clouds gather over global economy as world struggles to shake off crisis The Telegraph, Szu Ping Chan (6/10/15)
Five charts that explain what’s going on in a miserable global economy right now The Telegraph, Mehreen Khan (6/10/15)
IMF warns on worst global growth since financial crisis Financial Times, Chris Giles (6/10/15)
Global economic slowdown in six steps Financial Times, Chris Giles (6/10/15)
IMF Downgrades Global Economic Outlook Again Wall Street Journal, Ian Talley (6/10/15)

WEO publications
World Economic Outlook, October 2015: Adjusting to Lower Commodity Prices IMF (6/10/15)
Global Growth Slows Further, IMF’s latest World Economic Outlook IMF Podcast, Maurice Obstfeld (6/10/15)
Transcript of the World Economic Outlook Press Conference IMF (6/10/15)
World Economic Outlook Database IMF (October 2015 edition)


  1. Look at the forecasts made in the WEO October editions of 2007, 2010 and 2012 for economic growth two years ahead and compare them with the actual growth experienced. How do you explain the differences?
  2. Why is forecasting even two years ahead fraught with difficulties?
  3. What factors would cause a rise in (a) potential output; (b) potential growth?
  4. What is the relationship between actual and potential economic growth?
  5. Explain what is meant by hysteresis. Why may recessions have a permanent negative effect, not only on trend productivity levels, but on trend productivity growth?
  6. What are the current downside risks to the global economy?
  7. Why have commodity prices fallen? Who gains and who loses from lower commodity prices? Does it matter if falling commodity prices in commodity importing countries result in negative inflation?
  8. To what extent can exchange rate depreciation help commodity exporting countries?
  9. What is meant by the output gap? How have IMF estimates of the size of the output gap changed and what is the implication of this for actual and potential economic growth?

Real GDP depends on two things: output per hour worked and the number of hours worked. On the surface, the UK economy is currently doing relatively well, with growth in 2014 of 2.8%. After several years of poor economic growth following the financial crisis of 2007/8, growth of 2.8% represents a return to the long-run average for the 20 years prior to the crisis.

But growth since 2010 has been entirely due to an increase in hours worked. On the one hand, this is good, as it has meant an increase in employment. In this respect, the UK is doing better than other major economies. But productivity has not grown and on this front, the UK is doing worse than other countries.

The first chart shows UK output per hour worked (click here for a PowerPoint). It is based on figures released by the ONS on 1 April 2015. Average annual growth in output per hour worked was 2.3% from 2000 to 2008. Since then, productivity growth has stalled and output per hour is now lower than at the peak in 2008.

The green line projects from 2008 what output per hour would have been if its growth had remained at 2.3%. It shows that by the end of 2014 output per hour would have been nearly 18% higher if productivity growth had been maintained.

The second chart compares UK productivity growth with other countries (click here for a PowerPoint). Up to 2008, UK productivity was rising slightly faster than in the other five countries illustrated. Since then, it has performed worse than the other five countries, especially since 2011.

Productivity growth increases potential GDP. It also increases actual GDP if the productivity increase is not offset by a fall in hours worked. A rise in hours worked without a rise in productivity, however, even though it results in an increase in actual output, does not increase potential output. If real GDP growth is to be sustained over the long term, there must be an increase in productivity and not just in hours worked.

The articles below examines this poor productivity performance and looks at reasons why it has been so bad.


UK’s sluggish productivity worsened in late 2014 – ONS Reuters (1/4/15)
UK productivity growth is weakest since second world war, says ONS The Guardian, Larry Elliott (1/4/15)
UK productivity weakness worsening, says ONS Financial Times, Chris Giles (1/4/15)
Is the UK’s sluggish productivity a problem? Financial Times comment (1/4/15)
UK manufacturing hits eight-month high but productivity slump raises fears over sustainability of economic recovery This is Money, Camilla Canocchi (1/4/15)
Weak UK productivity unprecedented, ONS says BBC News (1/4/15)
Weep for falling productivity Robert Peston (1/4/15)
UK’s Falling Productivity Prevented A Massive Rise In Unemployment Forbes, Tim Worstall (2/4/15)


Labour Productivity, Q4 2014 ONS (1/4/15)
AMECO database European Commission, Economic and Financial Affairs


  1. How can productivity be measured? What are the advantages and disadvantages of using specific measures?
  2. Draw a diagram to show the effects on equilibrium national income of (a) a productivity increase, but offset by a fall in the number of hours worked; (b) a productivity increase with hours worked remaining the same; (c) a rise in hours worked with no increase in productivity. Assume that actual output depends on aggregate demand.
  3. Is poor productivity growth good for employment? Explain.
  4. Why is productivity in the UK lower now than in 2008?
  5. What policies can be pursued to increase productivity in the UK?

With the publication of the February 2014 Inflation Report the Bank of England has adjusted its forward guidance to the markets.

As we saw in Part 1 of this blog, the economy should soon fall below the 7% unemployment threshold adopted in the original forward guidance issued last August. But the Bank feels that there is still too much slack in the economy to raise interest rates when unemployment does fall below 7%.

The Bank has thus issued a new vaguer form of forward guidance.

The MPC’s view is that the economy currently has spare capacity equivalent to about 1%–1½% of GDP, concentrated in the labour market. Around half of that slack reflects the difference between the current unemployment rate of 7.1% and an estimate of its
medium-term equilibrium rate of 6%–6½%. The remaining slack largely reflects a judgement that employees would like to work more hours than is currently the case. Companies appear to be operating at close to normal levels of capacity, although this is subject to some uncertainty.

The existence of spare capacity in the economy is both wasteful and increases the risk that inflation will undershoot the target in the medium term. Moreover, recent developments in inflation mean that the near-term trade-off between keeping inflation close to the target and supporting output and employment is more favourable than at the time the MPC announced its guidance last August: CPI inflation has fallen back to the 2% target more quickly than anticipated and, with domestic costs well contained, is expected to remain at, or a little below, the target for the next few years. The MPC therefore judges that there remains scope to absorb spare capacity further before raising Bank Rate.

Just what will determine the timing and pace of tightening? The Bank identifies three factors: the sustainability of the recovery; the extent to which supply responds to demand; and the evolution of cost and price pressures. But there is considerable uncertainty about all of these.

Thus although this updated forward guidance suggests that interest rates will not be raised for some time to come, even when unemployment falls below 7%, it is not at all clear when a rise in Bank Rate is likely to be, and then how quickly and by how much Bank Rate will be raised over subsequent months. Partly this is because of the inevitable uncertainty about future developments in the economy, but partly this is because it is not clear just how the MPC will interpret developments.

So is this new vaguer forward guidance helpful? The following articles address this question.


Bank of England Governor Carney’s statement on forward guidance Reuters (12/2/14)
Why has Mark Carney tweaked forward guidance? The Telegraph, Denise Roland (12/2/14)
Interest rates: Carney rips up ‘forward guidance’ policy Channel 4 News (12/2/14)
Forward guidance version 2: will the public believe it? The Guardian, Larry Elliott (12/2/14)
Mark Carney adjusts Bank interest rate policy BBC News (12/2/14)
Mark Carney’s almost promise on rates BBC News, Robert Peston (12/2/14)
Did the Bank of England’s Forward Guidance work? Independent, Ben Chu (2/2/14)
Forward Guidance 2.0: Is Carney just digging with a larger shovel? Market Watch, The Tell (12/2/14)
The U.K. Economy: Five Key Takeaways Wall Street Journal, Alen Mattich (12/2/14)

Bank of England pages
Inflation Report, February 2014 Bank of England (12/2/14)
Monetary Policy Bank of England
MPC Remit Letters Bank of England
Forward Guidance Bank of England


  1. Summarize the new forward guidance given by the Bank of England.
  2. Why is credibility an important requirement for policy?
  3. What data would you need to have in order to identify the degree of economic slack in the economy?
  4. Why is it difficult to obtain such data – at least in a reliable form?
  5. What is meant by the ‘output gap’? Would it be a good idea to target the output gap?
  6. Is it possible to target the rate of inflation and one or more other indicators at the same time? Explain.