Meanwhile, the EU would have to embark on truly momentous changes in order to make the eurozone work. Banking union, fiscal union and political union must be put in place for the euro to survive.

We don’t know what effects this cocktail of changes will have upon European politics and economic performance – and hence on us.

“'We know that inside the EU we do not have full control of our destiny.’”

Roger Bootle

The overwhelming majority of the EU will be inside the euro, and what needs to be done to make the euro work would be the EU’s leading concern.

We do not know what things will be forced upon us by qualified majority voting. Moreover, with the referendum behind us, there is a good chance of a renewed push to get the UK into the euro. What have the calculations that produce the figure £4,300 a year got to say about this? The answer, of course, is precisely nothing.

And all this is before we take account of the dynamic effects and their political consequences. Perhaps after a Brexit our leaders would become enmeshed in rivalrous infighting and it would be impossible to put together an economic programme for national renewal.

But there is surely a good chance, as Michael Gove suggested last week, that by contrast EU departure would be the equivalent of a shot in the arm. 

Nor did the study have anything to say about the congestion and social costs implied by uncontrolled immigration, which are at the heart of so many people’s concerns about the EU.

Although the future is beset with uncertainty, about this issue we do know some things. We know that over recent decades the EU has been a comparative economic failure.

We know that unless something really radical happens, it is set to fall sharply in relative economic performance over the decades to come. We know that the EU is set to embark on a course of integration from which we aim to stand aside. We know that inside the EU we do not have full control of our destiny.

We know that inside the EU but outside the eurozone we will be marginalised.

I cannot say what all this means in terms of pounds per annum for the UK average household in 15 years’ time. But I can recognise the difference between a situation of opportunity and a pig in a poke.

David Fuller's view

Here is a PDF of Roger Bootle's column.

For myself and also my three-generation British family, staying in the EU feels like the inertia of running a loss on a trading position, hoping that it might improve but without any analytical evidence or conviction that it is likely to do so.