Confusing calculations: why politicians should stick to the basics

In his Conservative party conference speech in October, the Chancellor Philip Hammond said that the government had ‘announced an unprecedented £84 billion real-terms funding boost for the NHS’.

This had us scratching our heads at Full Fact - and we weren’t the only ones. The figure that we were familiar with was the £20.5 billion for the NHS that had been announced in June of this year.

So where had the other £63.5 billion suddenly appeared from? Never one to shy away from a mathematical challenge, we decided to investigate. 

Unhelpful maths

At the time the Treasury told us that the details of their £84 billion figure weren’t published anywhere. This was a bad start, and undermines the principles around equal access to government statistics and figures.

So instead we (and the Nuffield Trust) did our best to work out how it might be possible to arrive at a figure of £84 billion using published figures. Between us we spent nearly two weeks staring intensely at spreadsheets trying to understand the calculations.

What we eventually found was that it was possible to get to about £84 billion with the help of a bit of mind-bending maths, a dose of the Barnett formula and a sprinkling of pension contributions. When we then asked the Treasury again, armed with our calculations, they agreed they were roughly in line with theirs.  

But we also found that the calculation involved using some potentially misleading figures, such as money distributed to Scotland, Wales and Northern Ireland through the Barnett Formula that won’t necessarily go to the NHS as the governments there can spend it as they wish. It is also an unhelpful way of looking at the numbers; adding several years of spending together is simply not the normal way politicians talk about spending increases.

You can read the full details in our factcheck here.

The Chancellor has since used the figure again – it was one of the headlines in the text of his Budget speech in the House of Commons on 29 October (though on this occasion we think he misread the text in front of him, and appeared to say they were investing £8.4 billion in the NHS).

The Treasury have now published the relevant data as part of the Budget – though as far as we can tell it is not all published in one place, so still requires a bit of work to work out what the numbers mean. 

So why does this matter?

You may be wondering, if the £84 billion figure is technically correct, why are we making such a fuss?

Here’s why the number is a problem:

1. The figure is unhelpful and potentially misleading as we have set out above and in our factcheck.
2. Politicians should not be using figures in speeches before they can back them up publically – it shouldn’t take days of work by others to understand where they come from, and publishing them a month after they are used isn’t good enough.
3. Once a politician says something, it gets repeated in the press. This is especially true when the figure is presented without any context, which could lead to confusion and misunderstanding.

Stat makes no sense

This isn’t the first time we’ve come across politicians using complex maths or strange figures to make a point.

In May, we looked at the claims being made in the lead up to local elections about council tax. Both Labour and the Conservatives claimed constituencies run by their own parties had lower levels of council tax on average. The actual answer depends – you’ve guessed it – on how you do the maths.

Using inflated or unnecessarily complex figures can undermine public trust in politics, by making it harder for the numbers to be checked and scrutinised, and politicians need to stop doing it.  

We’ll keep working to make sure politicians stick to the basics and avoid confusing calculations whenever we can.