|Is the CBI right to claim |
the EU benefits UK GDP by 4-5%?
The CBI puts the net benefit at between £62bn and £78bn, or between 4% and 5% of UK GDP. This, it claims, is equivalent to £3,000 per household or £1,225 per individual. Credit to the CBI for trying to inject some hard numbers into the debate. However, putting a single figure on the costs and benefits of such a complex arrangement is notoriously difficult – as we ourselves know too well. The CBI does readily admit that in its report, and to be fair, very clearly qualifies its figure.
Still, there are at least three problems with this figure, which in combination means it should be taken with a huge pinch of salt.
Arbitrary extrapolation based on a highly limited literature review: Ultimately, the figure is taken from a literature review of previous estimates of the benefits. On average, the literature surveyed puts the net benefit of EU membership at between 2% and 3% of GDP. The review covers only five pieces of literature with the most recent one being from 2008. This is a very small pool of literature to draw from. More critically, the CBI goes onto assert,
“Since these studies are not mutually exclusive…it is not unreasonable to infer that the net benefit arising from EU membership is somewhat higher than 2–3%, perhaps in the region of 4–5% as a conservative estimate.”
It’s widely accepted that EU membership comes with unquantifiable benefits, but the CBI takes a massive leap of faith here. It seems to suggest that the net benefits of different aspects can be tallied up given that they are not mutually exclusive – and it may well be that dynamic effects triggered by, say, EU market access mean net benefits are often underestimated. However, curiously, the CBI provides no proper explanation or evidence for why it settled on 4% to 5%, leaving us guessing where this extra net benefit actually comes from. Having discussed this with the CBI, it’s clear that they have aggregated the net benefits of various aspects of the EU from different studies.
While there is logic in this approach, given the diverse nature of the studies it is tricky to simply add parts of the up, assuming that they work the same together as they do in isolation. After all, there is a reason why these studies have struggled to produce a clear figure for all the areas themselves. Once this approach was chosen more detail should have been included in the CBI report, even if it meant adding a statistical or economic annex (given the hugely sensitive nature of the EU cost-benefit debate).
No proper counterfactual is given: What are these net benefits measured against? Does the CBI assume that the UK outside the EU would be left with no trade deal and no single market access? If not, then the net benefit is presumably lower than the 4% to 5% identified. This is the classical shortcoming of most EU cost-benefit studies. In the CBI study, the problem is exacerbated by the fact that the various pieces of literature that it draws from will themselves have diverse counterfactuals.
Why the same rigour is not applied to its calculation of the net benefits of the EU is not clear. UKIP-types have mastered the art of measuring EU costs with no reference to a counterfactual (see here for a fine example). To a large extent, the CBI study falls into the same trap.
Benefits aren’t evenly distributed: Lastly, in an understandable attempt to present an easily digestible figure, the CBI converts its percentage number into pounds and presents it as an evenly distributed benefit over households and individuals. Of course, this is unlikely to be the real benefit felt by households or individuals, with any benefit distributed unevenly and in ways which are nearly impossible to measure.