Reissues: An order of magnitude (Mar 2010)

We know many people are bad at maths. However, most mistakes are easily spotted through experience and common sense. But sometimes, common sense is lacking: here I’m talking about the Conservatives gaff on teenage pregnancy.

So first, the Conservatives. A few days ago they launched a document called Labour’s Two Nations, that was supposed to show how there is great inequality in Britain today (let’s ignore the fact that the rise in inequality happened in the 1980s). What they wanted to point out was that under-18 girls in the most deprived areas are three times more likely to become pregnant than in the least deprived areas (Guardian). It’s not clear what this means with regards to ‘most deprived’ and ‘areas’ – I think it’s top and bottom centiles and districts – and I’m sure I could find a more shocking figure if I chose a harsher definition of most and least deprived. The mistake they did make, though, was to divide 54 by 1000 and come up with 54% not 5.4%. That’s if they did a calculation: some social statistics come as ‘per 1000′ or ‘per 10,000′ and it’s important to notice this.

This matters for two reasons. First, because 54% v 18% is a big difference and much more significant than a difference between 5.4% and 1.8% (significant though this is). Second, because anyone with any sense would realise that 54%, that is over half, is completely absurd.  Anywhere with 54% of its teenagers pregnant would have babies everywhere. Either the writer and editor just missed this, or they genuinely believed that there could be such a place and they are massively out of touch with normal life.