It should be noted there's something not quite right about the figures shown below: the totals don't come anywhere near the totals used by the Direct Marketing Association (as shown on the Junk mail volumes page). For instance, according to the Mail Media Centre - which published the below figures in a report called Mail volumes and response rates by industry sector 2010 - the total volume of addressed junk mail in 2009 was 1,43 billion. However, according to the Direct Marketing Association the total volume of addressed junk mail in 2009 was nearly 3.3 billion. That's more than twice as much junk mail! As per usual, both the Mail Media Centre and the Direct Marketing Association don't explain how the figures have been arrived at.

Here are the differences between the totals used by the Mail Media Centre and the Direct Marketing Association:

The percentage share per sector

The differences between the figures used by the Mail Media Centre and Direct Marketing Association are too large and too inconsistent (ranging from 43.6 to 55.6%) to extrapolate any useful information from them. Still, we may as well have a look at how the percentage shares of different sectors have changed in recent years. Most noteworthy is the drop in the share of the finance sector. In 2006, no less than 43% of all addressed junk mail was produced by the finance sector. By 2010 its share had fallen to 29.1%.

And here's the same table - but this time showing the year-on-year percentage increases / decreases. For instance, between 2006 and 2007 the volume of junk mail produced by the finance sector dropped by 11.9%. In the following year it dropped by another 26.2%, and so forth…

The industry doesn't publish any data about which sectors produce the most unaddressed junk mail.