THE GERS figures are stuck in a groove, and in recent times have not varied much from year to year. This does not make them any more satisfactory or reliable as a guide to the economic prospects of an independent Scotland.

When I give myself the chore of analysing them, I always go first to a particular pair of numbers. One is the UK spending deficit, which has been steadily falling from its peak during the financial crisis a decade ago. In fiscal year 2017-8 it went down to £39.4 billion, the lowest level since 2007. Only then do I take a look at the Scottish spending deficit, which this time showed a slight increase to £13.4bn.

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On that second criterion alone Scotland’s position actually worsened, which makes it odd for Unionist-inspired headlines to be screaming something about an improvement. There’s today’s fake news for you.

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The only improvement is in the gap between my chosen pair of numbers, not in the performance of the Scottish economy in an absolute sense. You would need to ask a Tory spin-doctor for an improvement of any other kind.

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But the weightier point is this: on my chosen pair of numbers, Scotland alone accounts for one-third of the UK deficit. Yet Scotland has only one-twelfth of the UK population. How can one-twelfth of the population generate one-third of the deficit?

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We know it must be expensive to provide roads and schools over large stretches of countryside where few people live. We know also about the Scots’ unhealthy habits, so that much more needs to be spent on treatments for lung cancer, cirrhosis of the liver and other horrible diseases. Even so, it beggars belief that a small population of five million could ramp up spending on such an enormous scale.

I’m especially suspicious of the way Unionists pile on the agony, assuming that an independent Scotland will still have the same sort of defence bill it has now as part of the vainglorious UK, complete with nuclear weapons and aircraft carriers.

We know the nuclear weapons are going to disappear. As for the aircraft carriers, the Queen Elizabeth was built at Rosyth, so clearly contributed to Scottish incomes and investment. At this moment it is sailing from Portsmouth to Norfolk, Virginia, and will seldom enter Scottish waters again. But for the next 50 years, as long as it is still afloat, one-twelfth of spending on it will be allocated to us.

Other types of spending are dealt with in an equally arbitrary way. We have no accurate measure of government spending in Scotland on business, environment, trade, transport and many more minor matters. So the GERS statisticians – doing the best they can – simply think of a number on the basis of population or some other analogy. This is true of all but one head of expenditure of 26 listed in GERS. Clearly, it would not take many errors to produce results wildly out of kilter with the truth.

From experience, we know that is what actually happens to these figures. Don’t believe them.