Why good news for GDP isn't necessarily good news for the Chancellor

The output gap is a strange and unpredictable beast, writes Nida Broughton.

The Coalition came into Government in 2010 with a plan to repair the public finances and set itself a target to eliminate the structural deficit. The ONS today published figures showing that GDP in the second quarter of this year is even higher than we thought, rising by 0.7 per cent rather than 0.6 per cent. But it isn’t clear if this is good or bad news for the Chancellor’s deficit strategy, because the structural deficit – and therefore the billions of cuts that George Osborne is pencilling in – is determined by small changes in a very slippery measure of the state of the economy: the output gap.

The Government’s structural deficit target is carefully worded to take into account the fact that part of the deficit – the “cyclical” part – will automatically disappear as the economy recovers. From a theoretical point of view, this makes sense: there is little point on focusing efforts on areas of spending that are going to fall anyway. The non-cyclical, “structural” part of the deficit – the part that will remain even when the economy is back on track is surely the part to be concerned about. 

So since 2010, the Office for Budget Responsibility (OBR), whose remit is to report on Government’s performance against its fiscal targets, has set about trying to measure the “output gap” – a measure of how far the economy has to recover.  The output gap is the difference between actual GDP and “potential” GDP. Potential GDP is the level of GDP that the economy could achieve if it were operating at “full capacity”.

But it has become increasingly clear that in practice, the output gap is just too difficult to measure. The OBR’s twice-yearly reports always show a comparison of the OBR’s estimate of the output gap against those made by other forecasters – including banks and independent forecasting houses. This provides a useful sense-check of the OBR’s figures. 

The last OBR report in March, showed, as it always has done, the huge range that different forecasters have come up with in measuring the output gap – ranging from -7.3 per cent to -0.9 per cent for 2013. To put this into context, just a two percentage point difference in the output gap estimate is enough to change the forecast structural deficit in the Government’s target year of 2018 by around £28bn – no small amount when the Government is looking to cut around £33bn after the election.

Earlier this month, the Bank of England, searching for a way to measure the state of the economy as part of its Forward Guidance, decided against the output gap, saying that:

“The output gap is unobservable and difficult to explain, and any estimate would be subject to substantial uncertainty.”

Instead, it plumped for unemployment as a measure. And now even as the economy is showing some signs of life, independent forecasters still can’t agree among themselves on what the positive growth figures mean for the output gap, as shown in the chart below. Of those releasing estimates after July’s surprise good news on growth from the ONS, two thought this meant the economy was now closer to potential. One thought that it was now further away – presumably taking the good news on GDP to be a sign of underlying productivity improvements that mean that the economy’s potential has expanded. And two kept their output gap estimate unchanged. 

Chart: Forecasts of the output gap in 2013

HM Treasury, Forecasts for the UK economy: a comparison of independent forecasts, August 2013

The question has to be asked: how useful is a public spending target that depends on such an uncertain measure of the economy? Perhaps recognising this, or perhaps because it made for a better statistic, George Osborne omitted to mention the “structural deficit” at all in his last Spending Review speech in June, referring instead to the overall deficit. And even though the structural deficit – on OBR forecasts - is due to go into surplus by 2016-17, George Osborne’s planned cuts stretch out to 2018. So does the Chancellor himself still believe in the usefulness of his target?

The Chancellor. Photograph: Getty Images

Nida Broughton is Senior Economist at the Social Market Foundation.

Photo: Getty
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What Jeremy Corbyn gets right about the single market

Technically, you can be outside the EU but inside the single market. Philosophically, you're still in the EU. 

I’ve been trying to work out what bothers me about the response to Jeremy Corbyn’s interview on the Andrew Marr programme.

What bothers me about Corbyn’s interview is obvious: the use of the phrase “wholesale importation” to describe people coming from Eastern Europe to the United Kingdom makes them sound like boxes of sugar rather than people. Adding to that, by suggesting that this “importation” had “destroy[ed] conditions”, rather than laying the blame on Britain’s under-enforced and under-regulated labour market, his words were more appropriate to a politician who believes that immigrants are objects to be scapegoated, not people to be served. (Though perhaps that is appropriate for the leader of the Labour Party if recent history is any guide.)

But I’m bothered, too, by the reaction to another part of his interview, in which the Labour leader said that Britain must leave the single market as it leaves the European Union. The response to this, which is technically correct, has been to attack Corbyn as Liechtenstein, Switzerland, Norway and Iceland are members of the single market but not the European Union.

In my view, leaving the single market will make Britain poorer in the short and long term, will immediately render much of Labour’s 2017 manifesto moot and will, in the long run, be a far bigger victory for right-wing politics than any mere election. Corbyn’s view, that the benefits of freeing a British government from the rules of the single market will outweigh the costs, doesn’t seem very likely to me. So why do I feel so uneasy about the claim that you can be a member of the single market and not the European Union?

I think it’s because the difficult truth is that these countries are, de facto, in the European Union in any meaningful sense. By any estimation, the three pillars of Britain’s “Out” vote were, firstly, control over Britain’s borders, aka the end of the free movement of people, secondly, more money for the public realm aka £350m a week for the NHS, and thirdly control over Britain’s own laws. It’s hard to see how, if the United Kingdom continues to be subject to the free movement of people, continues to pay large sums towards the European Union, and continues to have its laws set elsewhere, we have “honoured the referendum result”.

None of which changes my view that leaving the single market would be a catastrophe for the United Kingdom. But retaining Britain’s single market membership starts with making the argument for single market membership, not hiding behind rhetorical tricks about whether or not single market membership was on the ballot last June, when it quite clearly was. 

Stephen Bush is special correspondent at the New Statesman. His daily briefing, Morning Call, provides a quick and essential guide to domestic and global politics.