Stop Junk Mail's slogan currently is 'The Science of Junk Busting'. It captures a couple of projects I'm working on, one of which is getting some objective facts and figures about junk mail in the public domain.

That may not sounds like a huge job, but it is. Most statistics about advertising mail are collected by the Direct Marketing Association and Royal Mail, and they're extremely reluctant to share them with the general public. Or, to be more precise, they pick and choose what to research and what information to publish. Research is conducted with the aim of selling the 'direct mail channel' to potential advertisers and to convince Defra that self-regulation is working well. As a result we don't even know such basic things as how much junk mail is produced in the UK. Such figures would speak to the imagination and might make people want to cut back on unsolicited mail, which would of course be undesirable.

I'm pleased to say that a modest amount of facts and figures can now nevertheless be found on the Junk mail facts section of the Stop Junk Mail website. Because the junk mail industry is so bloody secretive none of the statistics can be verified, and some of the facts and figures are based on rather unscientific assumptions. But… we do now have a figure for the total volume of junk mail in the UK! In 2009, just under 12 billion pieces of junk mail were delivered to households and businesses.

The calculation nicely illustrates just how unscientific the facts are. The unknown variable in the calculation was the number of pieces of unaddressed junk mail. However, a report called Direct Marketing Material Waste Prevention 2009 gives us: a) the number of pieces of addressed junk mail produced in recent years; and b) the total volume of junk mail (both addressed and unaddressed) in tonnes for 2003, 2005, 2008 and 2009. Luckily, the report also gives us the average weight of a single piece of addressed and unaddressed junk mail (75.7 and 15.6 grams, respectively). And so we can work out how much unaddressed junk mail was distributed in 2009:

• calculate the total volume of addressed junk mail in tonnes
• subtract that figure from the total volume in tonnes (to get the volume in tonnes of unaddressed junk mail)
• divide that figure by the average weight of a single piece of unaddressed mail

Obviously, this is junk research. If the actual average weight of a piece of addressed junk mail is only 1 gram less – 74.7 grams instead of 75.7 – the volume of unaddressed mail increases by more than 200 million!

Yet, it does put a number on the scale of the problem. And, it makes it possible to calculate all the fun stuff. For instance, I can now tell you that the average household got 480 pieces of junk mail in 2009, of which 326 were unaddressed.