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