Why recessions followed by austerity can have a persistent impact

Economics students are taught from an early age that in the short run aggregate demand matters, but in the long run output is determined from the supply side. A better way of putting it is that supply adjusts to demand in the short run, but demand adjusts to supply in the long run. A key part of that conceptualisation is that long run supply is independent of short run movements in demand (booms or recessions). It is a simple conceptualisation that has been extremely useful in the past. Just look at the UK data shown in this post: despite oil crises, monetarism and the ERM recessions, UK output per capita appeared to come back to an underlying 2.25% trend after WWII.

Except not any more: we are currently more than 15% below that trend and since Brexit that gap is growing larger every quarter. Across most advanced countries, it appears that the global financial crisis (GFC) has changed the trend in underlying growth. You will find plenty of stories and papers that try to explain this as a downturn in the growth of supply caused by slower technical progress that both predated the GFC and that is independent of the recession caused by it.

In a previous post I looked at recent empirical evidence that told a different story: that the recession that followed the GFC appears to be having a permanent impact on output. You can tell this story in two ways. The first is that, on this occasion for some reason, supply had adjusted to lower demand. The second is that we are still in a situation where demand is below supply.

The theoretical reasons why supply might adjust to demand are not difficult to find. (They are often described by economists under the jargon word 'hysteresis'.) Supply (in terms of output per capita) depends on labour force participation, the amount of productive capital in the economy, and finally technical progress, which is really just a catch all for how aggregate labour and capital combine to produce output. A long period of deficient demand can discourage workers. It can also hold back investment: a new project may be profitable but if there is no demand it will not get financed.

However the most obvious route to link a recession to longer term supply is through technical progress, which connects to the vast literature under the umbrella of ‘endogenous growth theory’. This can be done through a simple AK model (as Antonio Fatas does here), or using a more elaborate model of technical progress, as Gianluca Benigno and Luca Fornaro do in their paper entitled ‘Stagnation traps’. The basic idea is that in a recession innovation is less profitable, so firms do less of it, which leads to less growth in productivity and hence supply. Narayana Kocherlakota has promoted this idea: see here for example.

The second type of explanation is attractive, in part because the mechanism that is meant to get demand towards supply - monetary policy - has been ‘out of action’ for so long because of the Zero Lower Bound (ZLB). (The ZLB also plays an important role in the Benigno & Fornaro model.) However for some this type of explanation currently seems ruled out by the fact that unemployment is close to pre-crisis levels in the UK and US at least.

There are three quite different problems I have with the view that we no longer have a problem of deficient demand because unemployment is low. The first, and most obvious, is that the natural rate of unemployment might be, for various reasons, considerably lower than it was before the GFC. The second is that workers may have priced themselves into jobs. In particular, low real wages may have encouraged firms to use more labour intensive techniques. If that has happened, it does not mean that the demand deficiency problem has gone away, but just that it is more hidden. (For anyone who has a conceptual problem with that, just think about the simplest New Keynesian model, which assumes a perfectly clearing labour market but still has demand deficiency.)

The third involves the nature of any productivity slowdown caused by lack of innovation. A key question, which the papers noted above do not directly address, is whether we are talking about frontier research, or more the implementation of innovation (for example, copying what frontier firms are doing). There is some empirical evidence to suggest that the productivity slowdown may reflect the absence of the latter. This is very important, because it implies the slowdown is reversible. I have argued that central banks should pay much more attention to what I call the innovation gap (the gap between best practice techniques, and those that firms actually employ) and its link to investment and aggregate demand.

All this shows that there is no absence of ideas about how a great recession and a slow recovery could have lasting effects. If there is a problem, it is more that the simple conceptualisation that I talked about at the beginning of this post has too great a grip on the way many people think. If any of the mechanisms I have talked about are important, then it means that the folly of austerity has had an impact that could last for at least a decade rather than just a few years.

Underestimating the impact of austerity

There have been many ideas put forward to explain the low growth in UK productivity, but among mainstream accounts the impact of austerity is not usually high up on the list of possibilities. I have talked before about what I call an ‘innovations gap’, and how the UK is currently suffering a particularly large innovations gap. The idea of an innovations gap can link inadequate demand, like austerity, to low productivity growth.

Let me use a very simple example to explain how an innovations gap can arise after a deep recession followed by austerity. Assume that improvements in technology and production techniques are constantly taking place, or being learnt from other firms/countries, but they need new investment to put them in place. This is what economists call embodied technical progress.

Imagine a firm where demand is not increasing. Will that firm invest to become more productive? Only if the additional profits it can make as a result of investing (suitably discounted) is greater than the cost of the investment. For this firm we therefore need quite a big innovation gap before it is worth its while to undertake investment and before its productivity increases.

Now imagine that demand increases. The firm now has to undertake some additional investment to increase its output. It makes sense to invest in techniques that embody the latest technology. The increase in demand leads to both higher investment (what economists call the ‘accelerator’) and higher productivity.

In a normal recovery from a recession, demand recovers rapidly (growth easily exceeds past trends), leading firms to invest in the latest technology. Any innovations gap that might have opened up in the recession is quickly closed. In contrast, a very slow recovery caused by austerity will reduce the need for investment, allowing a large innovations gap to open up.

This idea fits in with some recent work which suggests that productivity growth in ‘frontier’ firms (firms that already have relatively high productivity) has not slowed, and a gap has opened up between these frontier firms and laggards. (See also here.) This would make sense if the frontier firms are growing (because they are the most productive) but the laggard firms are not. Growing firms need to invest to expand, but stagnant firms are not expanding.

The same model could also suggest how wage led productivity growth could occur (see Ben Chu here for example). As most innovations are likely to be labour saving, then higher wages can increase the profits that come from any particular investment, without necessarily increasing the cost of that investment. So an increase in wages caused by an increase in the minimum wage, for example, could increase investment and therefore increase productivity. The other side of that coin is that the period of stagnant wage growth we have had since the recession provided no incentive for firms to invest in higher productivity techniques.

I doubt that this story explains more than a part of the UK’s productivity gap. In the UK investment in plant and machinery fell sharply in the recession, and has not yet recovered to pre-recession levels, but its decline is unlikely to be enough to explain a productivity standstill. (For an account of some other key factors that could explain the UK productivity puzzle, see here.) But if it explains even a little, it makes austerity a lot more costly.

One way of describing what I’m saying is that austerity influences supply as well as demand. You could say austerity ignores the accelerator as well as the multiplier, which is cute but does not capture the idea of embodied technical progress which is crucial to this argument. It is why it is always best to run a high pressure economy (see Martin Sandbu here who links to an interview between Jared Bernstein and Josh Bivens).

As I explain here, I do not use austerity as just another name for any fiscal consolidation, or fiscal consolidation involving cuts to spending. Fiscal consolidation need not reduce output for the aggregate economy if monetary policy is able to offset its impact. But if interest rates are at their lower bound, as they are once again in the UK [1], fiscal consolidation will reduce output and lead to another needless waste of resources. Since Brexit we have a second period of UK austerity. In assessing how costly this will be, we need to look not just at whether it creates a negative output gap, but also how it creates an innovations gap that reduces productivity.

[1] We know this, because the Bank is increasing the amount of QE.