Dianthus Medical Blog Archive

A zombie statistic is born

We're all familiar with zombie statistics: widely quoted, but hopelessly wrong, statistics that just refuse to die.

I think I've just witnessed the birth of a new one. Thanks to Anna Sharman on Twitter, my attention was recently drawn to a rather implausible statistic on the Guardian website: "The self-employed face average debts of 18.6 times their annual income".

Wow. Even with today's low interest rates, that means you'd probably be spending your entire income on servicing the interest on your debt, with nothing left over for things like food.

Is that even remotely plausible?

I didn't think so. But a quick bit of digging revealed the source of this statistic: the debt charity Step Change. Step Change had commissioned a report on the levels of debt faced by people seeking help from the charity, which did indeed find an average debt of 18.6 times annual income.

But the really, really important thing to realise here, is that this is the average level of debt owed by those seeking help from the charity. This is really not the same as the average level of debt held by self employed people in general. I think it's safe to assume that the subset of self employed people who seek help from a debt charity will have very much larger debts than a random sample of all self employed people.

That crucial difference, however was completely ignored when the Guardian wrote it up into a scary headline. And so a new zombie statistic is born. Like its horror-movie-inspired namesake, I suspect it may not be that easy to kill.

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