When he wasn’t crushing chalk in his fists at my inability to grasp binary notation, I remember my old maths teacher Mr Morton (Beaky) trying to impress on me the importance of numbers. Numbers, he used to suggest, were solid, sensible and reliable whereas words could have more than one meaning and were inscrutable and slippery. Words could be entertaining and amusing, yes. But numbers were truth.

I think it was the first time I received a press release from a politician that I realised how wrong Mr Morton was. Quite quickly I could see that just because something has pound signs or percentages doesn’t necessarily mean it’s accurate and the SNP has given us some juicy examples. Such as: £97m equals the cost of two ferries. Or: £11,000 equals constituency business on an iPad. Or most hilariously of all: 36% equals a mandate for a referendum.

Another particularly egregious example, although it actually goes back about 17 years, is a figure the SNP loves, or used to. Scotland, they would say, has 25% of Europe’s potential offshore wind resource and imagine, they’d tell us, what it would be like if an independent Scotland was allowed to tap into that resource rather than having it squandered by Westminster. It was a claim that was often repeated, not least by Ian Blackford and Stephen Flynn; 25% equals happy days!

The only problem is the 25% figure wasn’t true and we finally know this for sure thanks to some dogged work by the pro-UK group These Islands. These Islands also calculated what the actual figure for Scotland’s offshore wind potential is and it’s quite a bit less than 25% I’m afraid. It’s 6.8%.

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Sam Taylor of These Islands talked me through how they got to the 6.8% and it’s worth going into because it exposes two things. First, how numbers can be fiddled. And second, how the SNP (and most other governments to be fair) promote some things even if untrue and bury others even if true.

What happened in the case of the offshore wind estimate was that the Scottish Government – having promised to update parliament on the true figure – did eventually, sort of admit the truth but only in the annex to a letter to a committee, which is rather like the Vogons in Hitchhiker’s Guide to the Galaxy lodging their planning application at the bottom of a locked filing cabinet in a disused lavatory with a sign on the door saying ‘Beware of the Leopard.’

What the annex said was this: “11GW of offshore wind in Scotland would represent 22% of the UK ambition for 50GW of offshore wind by 2030, and approximately 10% of the EU ambition for 111GW offshore renewables by 2030.” But Mr Taylor points out Scotland’s figure can only be seen as 10% if you compare it to the EU only (111GW). Once you add the UK (50GW), you get 161GW, and the Scottish 11GW is 6.8% of 161GW not 10%. The SNP are doing it this way to deliberately confuse people, says Mr Taylor.

The Herald:

And the SNP has form here. In 2022, Humza Yousaf, the then health secretary, unveiled a web portal where patients could see waiting times in their area. But some surgeons expressed concern the figures gave a false impression and after looking into it, the UK Office for Statistics Regulation concluded patients might experience “a much longer wait than is suggested by the figures”.

More recently, the Government also published a report which said that since the introduction of minimum pricing, alcohol deaths had fallen by over 10% and hospital admissions directly linked to alcohol consumption by 4.1%. But the UK Statistics Authority cast doubt on the way the report was written and the SNP was forced to alter it.

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All of this matters not because it proves numbers can be misleading (we know that) but because it underlines the responsibility of politicians to use numbers responsibly. If you say something is 25% of something else: prove it. And if you know the 25% figure is wrong: admit it. My old maths teacher told me numbers were solid, sensible and reliable. But the people who use them often aren’t. So look out. Beware. And stay alert.