Averages are interesting. The problem is they aren’t much more than that.

It’s interesting to know that your daily average number of visitors is 49,000. Or that the average visitor sees 4.2 pages. Or that your Yahoo Search Marketing paid search click-through-rate average is 2.1%.

But before moving these numbers from interesting to important, or accurate, or actionable, you should always take the time to look inside them. Because the average may cover up some huge difference in the numbers which lie below.

That’s exactly what is apparently happening with the age-old banner ad click-through-rate numbers now that some research has been done into exactly who was clicking on those ads. The report documents:

…just 6% of the online population yet account for 50% of all display ad clicks. While many online media companies use click-through rate as an ad negotiation currency, the study shows that heavy clickers are not representative of the general public. In fact, heavy clickers skew towards Internet users between the ages of 25-44 and households with an income under $40,000. Heavy clickers behave very differently online than the typical Internet user, and while they spend four times more time online than non-clickers, their spending does not proportionately reflect this very heavy Internet usage. Heavy clickers are also relatively more likely to visit auctions, gambling, and career services sites – a markedly different surfing pattern than non-clickers.

 The problem of averages is rampant in paid search analytics, where CPCs, CTRs, and conversion rates as well as more important numbers such as ROI are often seen in ‘roll-ups’ of campaigns or ad-groups, or some type of classifications. It’s handy to see these averages, but don’t forget to dig a little deeper before taking any resulting actions.