Category: Economics for Business: Ch 22

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End of the line

HS2 has been cancelled north of Birmingham. The prime minister, Rishi Sunak, announced this at the Conservative Party conference on 4 October, some 13 years after the plan was adopted by the Labour government to build a new high-speed railway from London to Birmingham, which then would branch into two legs – one to Manchester and one to Leeds. The initial budget for this was £15.8bn to £17.4bn. When it came to power, the Conservative-Liberal coalition government ordered a review of the plan. In light of this, the government gave the green light in January 2012 for the full Y-shaped project to go ahead. The London–Birmingham leg was planned to open in 2026 and the two northern legs from 2033.

The project was divided into two phases: Phase 1 to Birmingham and Phase 2 to Manchester and Leeds. The Phase 1 parliamentary bill became law in February 2017 and soon after that, various construction contracts were signed. After some delays, preparation for construction work began in June 2019. There was growing doubt, however, about the viability of the northern legs.

On becoming prime minister in 2019, Boris Johnson ordered an independent review of the project after estimates that the costs of the full project would be some £88bn. The review, chaired by Douglas Oakervee, was published in December 2019 (for a link, see list of reports below). It found that costs (in 2015 prices) were likely to be between £62bn and £69bn. Nevertheless, it concluded that the project should proceed: that the original rationale for HS2 still held; that there were:

no shovel-ready alternative investments in the existing network that were available: if HS2 were to be cancelled, many years of planning work would be required to identify, design and develop new proposals; that the upgrading of existing lines would also come at a high passenger cost with significant disruption; that there would be serious consequences for the supply chain, the fragile UK construction industry and confidence in UK infrastructure planning if HS2 were to be cancelled at this late stage.

In February 2020, the prime minister announced that HS2 would go ahead, including the legs to Manchester and Leeds. The Department for Transport published a document (see source line to the following table) giving the full business case for Phase 1 and the outline case for Phase 2. The document itemised the costs and benefits as estimated at the time.

Source: Full Business Case: High Speed Two, Table 2.9, Department for Transport (April 2020)

Box 12.6 in Economics (eleventh edition) and Case study 8.16 on the Essentials of Economics (ninth edition) student website looks at these costs and benefits. The above table is taken from the box/case study. Net transport benefits (present value at 2015 prices) were estimated to be £74.2bn. These include benefits to passengers from shorter journey times, greater reliability, greater connectivity and less crowding, and reduced congestion on roads. They also include other benefits, such as a reduction in carbon emissions and a reduction in road accidents. Net benefits also include the wider benefits from greater connectivity between firms (resulting in increased specialism, trade and investment), greater competition and greater labour mobility. These wider benefits were estimated to be £20.5bn, giving total net benefits of £94.7bn.

Total costs to the government were estimated to be £108.9bn and revenues from fares to be £45.4bn, giving total net costs of £63.5bn. This gave a benefit/cost ratio of 1.5 (£94.7bn/£63.5bn). In the light of these findings, the government announced in September 2020 that the main work on the London to Birmingham leg would begin, despite the Public Accounts Committee’s finding that the project was badly off course and lacking in transparency.

Concern was expressed over whether the Leeds leg would go ahead, but in May 2021, the transport secretary, Grant Shapps, confirmed that it would be completed. However, with the publication of the Integrated Rail Plan in November 2021 (for a link, see list of reports below), the government decided that the eastern leg of HS2 would no longer reach Leeds but instead end in the East Midlands. Then in June 2022, the link between the HS2 line near Manchester and the West Coast Main Line was scrapped. This would have allowed HS2 trains to reach Scotland.

In early 2023, it was announced that the building of the terminus at Euston was being put on hold. Many interpreted this as meaning that it was being scrapped, with trains terminating at Old Oak Common, some six miles from Central London.

Finally, as we have seen, HS2 north of Birmingham has now been scrapped and the government is seeking private-sector funding to build the terminus at Euston and complete the line from Old Oak Common.

Arguments for scrapping the northern legs

The main argument given by the government was that projected costs have risen substantially above original estimates and that by cancelling the Manchester and east Midlands legs, the money saved could be better used elsewhere. The argument is one of opportunity cost. The cost of going ahead would mean not going ahead with better-value alternatives.

The government claims that £36bn will be saved and that this will be diverted to rail, road and other transport projects, primarily (although not exclusively) in the north of England. The money would be spent between 2029 and 2040. Projects include spending additional money on the planned upgrading of the rail link between Manchester and Liverpool, Sheffield, Leeds and Hull; building a new station at Bradford; developing a mass transit system for Leeds and its surroundings; a £2.5bn fund for improved transport for smaller cities, towns and the countryside in the north of England; extra funding for transport in the east and west Midlands, including funding a Midlands Rail Hub. Out of the £36bn, £6.5bn would be for projects elsewhere, including road improvement.

In order to judge whether the diversion of funds represents a better use of money, a full analysis of costs and benefits of the various projects would need to be conducted and compared with an updated cost–benefit analysis of continuing with the legs to Manchester and the east Midlands and possibly reinstating the Leeds leg too.

One possible benefit for the government is a political one. It hopes that promising more local projects rather than HS2 will appeal to the electorate in large parts of the north of England who are suffering from poor and unreliable transport links. However, most of these projects will be started well beyond the next election and this political gain may turn out to be small. Indeed, cancelling HS2 may breed cynicism, with people wondering whether any promised new projects will actually be delivered.

Arguments against scrapping the northern leg(s)

The benefits originally identified from HS2 will now be lost. It is not just that the northern legs of HS2 would have provided faster travel to Manchester and Leeds, but the new lines would have reduced congestion for slower trains and freight on existing lines. This has been the experience in countries such as Japan and Spain, which have invested heavily in new, separate high-speed lines.

When the line is completed to Birmingham, the HS2 trains will be able to continue north of Birmingham on existing lines. But these lines are heavily congested, which will limit the number of HS2 trains that can use them. Also they will be restricted to 110 mph on these lines as they have no tilting mechanism. Also they will have a maximum capacity of only 550 seats (a single train set) as the platforms at Manchester Piccadilly cannot accommodate double-set trains. The existing Pendalino trains on the West Coast mainline can travel at 125 mph as they do have the tilting mechanism and they have a higher capacity of 607 seats.

Then there are the signals that cancellation sends to industry about whether governments can be trusted to follow through on public-sector projects. Many business had expanded or relocated to places near the HS2 routes. Many others will wonder whether the promised new projects will go ahead. Indeed, shortly after giving a list of the projects (some of which had already been built or were being built), the list was removed from the government website. There is already a mood of scepticism amongst the electorate. Polling following the initial announcement showed that a majority believed that it was unlikely that the Conservatives would deliver the other projects if they won the next election.

The opportunity cost argument that the money would be better spent on alternative transport projects is predicated on various assumptions. One is that the money will actually be spent, which, as we have seen, people consider doubtful. Another is that the only choice is either spending a fixed pot of money on the northern leg(s) of HS2 or spending it on the alternative projects announced by the prime minister. It could be argued that the government should proceed with both the full HS2 and these other projects, and fund it by extra taxation. Investment as a percentage of GDP is low in the UK compared with other countries. Over the past 10 years, it has averaged 17.8% in the UK. This compares with 21.0% in the USA, 21.5% in Germany, 23.7% in France and 25.4% in Japan. Also, public-sector investment is low in the UK compared with that in other countries.

Assessing the arguments

Many of the costs and benefits of long-term projects, such as HS2, occur many years hence. There is, therefore, a great deal of uncertainty over their magnitude. This makes it extremely difficult to reach a clear conclusion over the desirability of cancelling HS2 north of Birmingham or continuing with it. Under such circumstances, politics tends to dominate decision making.

Articles

Government Press Release

Reports

Questions

  1. Why have the costs of HS2 (in real terms) risen substantially since the first estimates in 2012?
  2. Identify the types of environmental costs and benefits of the full Y-shaped HS2 project. Why might such costs and benefits be difficult to measure?
  3. Is the opportunity of cost of proceeding with the full Y-shaped HS2 a range of other transport projects? Explain.
  4. Find out the level of public-sector investment expenditure as a percentage of (a) total government expenditure and (b) GDP in some other developed countries and compare them with the UK. Comment on your findings.
  5. Should the decision whether or not to go ahead with the Manchester and east Midlands legs have been delayed until a new updated cost–benefit analysis had been conducted?
  6. If most of the benefits from the originally planned HS2 will be now be lost with the line ending at Birmingham, should this leg to Birmingham also be cancelled, even though many of the costs have already been incurred? Explain your reasoning.
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Global boiling – why not take urgent action now?

The global average temperature for July 2023 was the highest ever recorded and July 3rd was the world’s hottest day on record. We’ve seen scenes of wildfires raging across much of southern Europe, people suffering searing temperatures in south-west USA, southern India and western China, flash floods in South Korea, Japan and eastern USA. These are all directly related to global warming, which is causing weather systems to become more extreme. And as the planet continues to warm, so these problems will intensify.

The Secretary General of the United Nations, Antonio Guterres, in a press conference on 27 July warned that:

Climate change is here. It is terrifying. And it is just the beginning. The era of global warming has ended; the era of global boiling has arrived. The air is unbreathable. The heat is unbearable. And the level of fossil-fuel profits and climate inaction is unacceptable. Leaders must lead. No more hesitancy. No more excuses. No more waiting for others to move first. There is simply no more time for that.

The environmental, human, social and economic impact of global warming is huge, but concentrated on just part of the world’s population. For many, a more variable climate is at worst an inconvenience – at least in the short term. But it is the short term that politicians are most concerned about when seeking to win the next election.

Tackling climate change requires action to reduce carbon emissions now, even though the effects take many years. But one person’s emissions make only a minuscule contribution to global warming. So why not be selfish and carry on driving, flying off on holiday, using a gas boiler and eating large amounts of red meat? This is what many people want to do and governments know it. Many people do not like green policies as they involve sacrifice. Examples include higher fuel prices and restrictions on what you can do. So, despite the visions of fires, floods and destruction, governments are wary about raising fuel taxes, airport duties and charges to use old high-emission cars in cities; wary about raising taxes generally to provide subsidies for sustainable power generation; wary about banning new oil and gas fields that would reduce reliance on imported fuel.

Because the external costs of carbon emissions are so high and global, government action is required to change behaviour. Education can help and scenes of devastation from around the world may change the hearts and minds or some people. Also, the prospect of profits from cleaner and more fuel-efficient technology can help to spur innovation and investment. But to meet net zero targets still requires policies that are unpopular with many people who might be inconvenienced or have to pay higher petrol, energy and food prices, especially at a time when budgets are being squeezed by inflation.

Part of the problem is a distributional one. The people most affected by the cost-of-living crisis and higher interest rates are those on lower incomes and with higher debts. Politicians know that it will be hard to win the votes of such people if they are faced with higher green taxes. As elections approach, politicians are likely to backtrack on many environmental commitments to appeal to such people.

This is beginning to happen in the UK, with the government declaring that it is on the side of the motorist. Indeed, Rishi Sunak has just announced that the government will authorise more than 100 new licenses for new oil and gas wells in the North Sea. This is despite the United Nations, various other international bodies, climate scientists and charities calling for a halt to all licensing and funding of new oil and gas development from new and existing fields. The government argues that increased North Sea production would reduce the reliance on imported oil.

Video

Articles

Questions

  1. In what sense is the environment a ‘public good’? How is the concept of externalities relevant in analysing the private decisions made about the use of a public good?
  2. How may game theory be used to help understand the difficulties in reaching international agreement about climate change policies?
  3. What is meant by ‘net zero’? Is carbon capture and storage an acceptable alternative to cutting carbon emissions?
  4. In what ways could policies to tackle climate change be designed to reduce income inequality rather than increase it?
  5. What are the arguments for and against banning (a) petrol and diesel cars; (b) gas boilers; (c) fossil-fuel power stations? How much notice should be given if such bans are to be introduced?
  6. What is meant by ‘nudge theory’? In what ways could people be nudged into making greener decisions?
  7. What are the arguments for and against granting new licences for North Sea oil and gas drilling? Explain where you feel the balance of the arguments lies.
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Tackling climate change: ‘Everything, everywhere, all at once’

The United Nations International Panel on Climate Change (IPCC) has just published its most comprehensive report so far. It finds that ‘human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming’. This has led to widespread and rapid changes in climate and biodiversity and to more extreme weather patterns, such as droughts, floods and hurricanes. What is more, the distribution of these effects is uneven, with communities who have contributed the least to current climate change being disproportionately affected.

At the 2015 COP21 climate change conference in Paris (see also), it was agreed to adopt policies to limit the increase in global temperatures to ‘well below’ 2°C above pre-industrial levels and to make an effort to limit it to 1.5°C. Global temperatures have already risen 1.1°C above 1850–1900 levels and are set to reach 1.5°C in the early 2030s. Every increment of global warming will intensify ‘multiple and concurrent hazards’.

Deep, rapid and sustained reductions in emissions would slow down the rise in global temperatures, but even with such reductions, temperatures will still exceed 1.5°C in the next few years and, even under the best-case scenario, would not fall below 1.5°C again until the end of the 21st century. Under more pessimistic scenarios, global temperatures could rise to 2.7°C above pre-industrial levels by the end of the century under an intermediate greenhouse gas emissions scenario and to 4.4°C under a very high emissions scenario. Anything above 2°C would be likely to have catastrophic effects. The longer countries wait to take action, the greater the rise in global temperatures and hence the greater the damage and the more costly it will be to rectify it.

‘For any given future warming level… projected long-term impacts are up to multiple times higher than currently observed (high confidence). Risks and projected adverse impacts and related losses and damages from climate change escalate with every increment of global warming (very high confidence). Climatic and non-climatic risks will increasingly interact, creating compound and cascading risks that are more complex and difficult to manage (high confidence).’ (Paragraph B2)

But the report is not all ‘doom and gloom’. It is possible to limit global warming to 1.5°C or only a little over by making rapid, deep and, in most cases, immediate greenhouse gas emissions reductions in all sectors and reaching net zero emissions in the early 2050s. Science and technology have the answers – answers that are now much cheaper and more available than back in 2015 when the 1.5°C target was agreed. But what it does require is doing ‘everything, everywhere, all at once’. And that requires political will and the right economic incentives.

The politics and economics of achieving net zero

In terms of the politics, there is general global agreement by governments about the likely effects of climate change. And most governments agree that action needs to be taken. However, there are three key political problems.

The first is that the costs of action will be borne now, while the benefits of action will accrue over a much longer period of time. This links to the second problem – the mismatch between the lives of governments and the long-term effects of climate change. If governments put off doing anything now and merely promise that something will be done in the future, they will not have to take unpopular actions, such as raising taxes on energy, private transport and certain goods or banning various activities. Future governments will have to sort things out, by when, although the problems will be greater, the existing politicians will no longer be in power.

The third problem concerns the distribution of the costs and benefits of action. The major emitters of carbon are the rich countries, while the major sufferers are poor people in countries subject to drought, flooding and rising sea levels. Not surprisingly, who should cut down on emissions and pay for the mitigation necessary in many of the poorer countries is a difficult political issue, which is why it’s much easier to say what needs to be achieved overall than precisely what measures should be taken by which countries.

These problems reflect the fact that many, if not most, of the environmental costs of production and consumption are external costs – costs borne, not by the direct producer or consumer, but by other people at other places and/or in the future.

Nevertheless, the relative costs of moving to greener production and consumption are falling. The costs of renewable energy, including solar power, onshore and offshore wind and hydroelectric power are falling relative to that generated from fossil fuels. At the same time, the take up of electric cars is likely to continue rising as battery technology improves. This does, of course, require an increase in charging infrastructure. Domestic heat pump technology is improving and home insulation methods are becoming more efficient.

Persuading consumers and firms to take account of environmental externalities could in part be achieved by education. It makes it much easier for politicians to take appropriate action now if their populations are on board. There has been increasing awareness over the years of the environmental impact of people’s actions. People have become more willing to take responsibility for the world that future generations will inherit. This is helped both by education in schools and colleges and by frequent items in the media.

But incentives also have a major part to play. To internalise environmental externalities, external costs could be taxed and external benefits subsidised.

The effect of a carbon tax on production

The use of taxes to reduce activities with negative environmental externalities is illustrated in the diagram (click here for a PowerPoint). It takes the case of carbon emissions from coal-fired electricity generation in a large country. To keep the analysis simple, it is assumed that all electricity in the country is generated from coal-fired power stations and that there are many such power stations, making the market perfectly competitive.

It is assumed that all the benefits from electricity production accrue solely to the consumers of electricity (i.e. there are no external benefits from consumption). Marginal private and marginal social benefits of the production of electricity are thus the same (MPB = MSB). The curve slopes downwards because, with a downward-sloping demand for electricity, higher output results in a lower marginal benefit (diminishing marginal utility).

Competitive market forces, with producers and consumers responding only to private costs and benefits, will result in a market equilibrium at point a in the diagram: i.e. where demand equals supply. The market equilibrium price is P0 while the market equilibrium quantity is Q0. However the presence of external costs in production means that MSC > MPC. In other words, MEC = b – a.

The socially optimal output would be Q* where P = MSB = MSC, achieved at the socially optimal price of P*. This is illustrated at point d and clearly shows how external costs of production in a perfectly competitive market result in overproduction: i.e. Q0 > Q*. From society’s point of view, too much electricity is being produced and consumed.

If a carbon tax of d – c is imposed on the electricity producers, it will now be in producers’ interests to produce at Q*, where their new private marginal costs (including tax) equals their marginal private benefit.

But this brings us back to the politics of measures to reduce emissions. People do not like paying higher taxes. In his latest Budget, the UK Chancellor, Jeremy Hunt, decided not to raise fuel duties by the 12p that had been previously planned, despite fuel prices having recently fallen. Meanwhile, charging prices for electric cars have risen.

Other economic measures

A simpler method for dealing with environmental externalities is ban certain activities that omit CO2. For example, in the UK there will be a ban on the sale of new petrol and diesel cars and vans from 2030 (with the exception of some low-emission hybrids until 2035). In the EU there will be a similar ban from 2035. Clearly, such measures are only suitable when there are non-emitting alternatives.

Another alternative is a cap-and-trade system, such as the European Emissions Trading Scheme. It involves setting quotas for emissions and allowing firms which manage to cut emissions to sell their surplus permits to less efficient firms. This puts a price pressure on firms to be more efficient. But the quotas (the ‘cap’) must be sufficiently tight if emissions are going to be cut to desired levels. Nevertheless, it is an efficient way of cutting emissions as it gives a competitive advantage to low-emission producers.

Conclusion

If the problem of global warming is to be limited to 1.5°C, or only very little above, multiple solutions will need to be found and there must be a combination of political will, economic incentives and the mobilisation of scientific and technical know-how. As the Secretary-General of the United Nations, António Guterres, stated in launching the new report:

This report is a clarion call to massively fast-track climate efforts by every country and every sector and on every timeframe. In short, our world needs climate action on all fronts – everything, everywhere, all at once.

Report

Videos

Articles

Questions

  1. Why might countries not do ‘everything, everywhere, all at once’ to avert climate change?
  2. What might an optimist conclude from the ICC report?
  3. To what extent is climate change an economic problem?
  4. On a diagram similar to the one above, show how a subsidy could be used to internalise positive externalities.
  5. How might countries reduce the consumption of fossil fuels in the most efficient way? Are they likely to want to do this? Explain.
  6. Is a ‘cap-and-trade’ (tradable permits) system (a) an effective means of reducing emissions; (b) an efficient system?
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Tackling the menace of fly-tipping

If it costs to dispose of waste, there is the danger that people may resort to fly-tipping – the illegal dumping of waste in the countryside or on the streets. But several local authorities have indeed been charging for the disposal of building/DIY waste, with the inevitable consequences of huge quantities of dumped rubbish.

Apart from being an eyesore and damaging the environment, fly-tipped waste can be a health hazard, often containing toxic materials, such as asbestos and chemicals. According to the UK government, in 2020/21 there were over 60 000 incidents of fly-tipping of construction, demolition and excavation material, costing an estimated £392 million. In addition, people leave black bags of household waste and single items, such as mattresses, on the roadside.

The external costs are considerably greater than the benefits to those doing the dumping, but because the costs are largely external, people are encouraged to fly-tip, especially if they think that they are unlikely to be caught. Many householders are happy to pay low rates to have their DIY waste disposed of and ‘ask no questions’ about what will happen to it.

It is clearly socially efficient to stop fly-tipping. One solution is to enforce the law more rigorously and to introduce stiffer penalties. Increasingly, local authorities and private landowners are installing CCTV cameras to identify people doing the tipping. To be effective, the cameras must be out of reach. Also, the police must then follow up any cases and arrest and charge the culprits.

An alternative is to provide free disposal at council tips. The UK government has launched a consultation on a proposal to prevent local authorities from charging for the disposal of DIY waste. This still involves an externality in that the costs of disposal are not being borne by the person creating the waste, but clearly the size of the negative externality is considerably less than if the waste had been fly-tipped.

Selected local authorities can apply for new grants totalling £450 000 to help fund the provision of free DIY waste disposal and to install systems, such as CCTV and automatic number-plate recognition, to catch fly-tippers in action.

Devising policies to reduce externalities often involves understanding the incentive mechanisms which encourage people to engage in such activities in the first place and then making it in people’s interests not to engage in them in the future.

Videos

Articles

Government publications

Questions

  1. Draw a diagram to illustrate how the consumption of products with large negative externalities is considerably above the socially efficient level.
  2. Compare the relative advantages and disadvantages of the various policy alternatives to tackle fly-tipping that are discussed in the articles.
  3. Are there any ‘nudges’ that could be used to prevent fly-tipping?
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The future of shipping and trade

Shipping and supply chains generally have experienced major problems in 2021. The global pandemic disrupted the flow of trade, and the bounce-back in the summer of 2021 saw supply chains stretched as staff shortages and physical capacity limits hit the transport of freight. Ships were held up at ports waiting for unloading and onward transportation. The just-in-time methods of delivery and stock holding were put under considerable strain.

The problems were compounded by the blockage of the Suez canal in March 2021. As the blog, JIT or Illegit stated “When the large container ship, the Ever Given, en route from Malaysia to Felixtowe, was wedged in the Suez canal for six days in March this year, the blockage caused shipping to be backed up. By day six, 367 container ships were waiting to transit the canal. The disruption to supply cost some £730m.”

Another major event in 2021 was the Glasgow COP26 climate conference and the growing willingness of countries to commit to decarbonising their economies. But whereas electricity can be generated from renewable sources, and factories and land transport, such as cars, vans and trains, can run on electricity, it is not so easy to decarbonise shipping, especially for long journeys. They cannot plug in to the grid or draw down from overhead cables. They have to carry their own fuel sources with them.

So, have the pandemic and the Ever Given incident exposed weaknesses in the global supply chain and in shipping in particular? And, if so, in what ways is shipping likely to adapt? And will the pressure to decarbonise lead to a radical rethinking of shipping and long-distance trade?

These are some of the issues considered in the podcast linked below. In it, “Shipping strategist Mark Williams tells Helen Lewis how examining the challenge of decarbonising shipping reveals a future which looks radically different to today, in a world where population, oil extraction and economic growth have all peaked, and trade is transformed”.

Listen to the podcast and have a go at the questions below which are based directly on it.

Podcast

Articles

Questions

  1. Why should we care about the shipping industry?
  2. What lessons can be drawn from the Ever Given incident?
  3. What structural changes are needed to make shipping an industry fit for the long-term demands of the global economy?
  4. Distinguish between just-in-time supply chains and just-in-case supply chains.
  5. What are ‘reshoring’ and ‘nearshoring’? How have they been driven by a growth in trade barriers?
  6. What are the implications of reshoring and nearshoring for (a) globalisation and (b) the UK’s trading position post-Brexit?
  7. What is the contribution of shipping to global greenhouse gas emissions? What other pollutants are emitted from the burning of heavy fuel oil (or ‘bunker fuel’)?
  8. What levers exist to persuade shipping companies to decarbonise their vessels?
  9. What alternative ‘green’ fuels are available to power ships?
  10. What are the difficulties in switching to such fuels?
  11. What economies of scale are there in shipping?
  12. How do the ownership patterns in shipping benefit decision making and change in the industry?
  13. Are ammonia or nuclear power the answer to the decarbonisation of shipping? What are their advantages and disadvantages?
  14. Why are President Xi’s views on the future of shipping so important?
  15. How will the decarbonisation of economies affect the demand for shipping?
  16. What is likely to happen to Chinese demand for iron ore and coking coal over the coming years? What effect will it have on shipping?
  17. How and by how much is the European Emissions Trading System likely to contribute to the decarbonisation of shipping?
  18. What is the Sea Cargo Charter? What difference is it likely to make to the decarbonisation of shipping?
  19. In what ways do cargo ships optimise productivity?
  20. What impact is slowing population growth, or even no population growth, likely to have on shipping?