Naturally, any business that runs PPC marketing campaigns keeps a careful eye on Analytics. One particularly pertinent figure that will be under constant observation is the average cost per acquisition (CPA), which can give rise to all sorts of problems.
Averages appear everywhere and in all walks of life. Almost everyone uses the phrase, 'the law of averages' in conversation at some point in their lives, often relating to what they hope will happen - rather than what actually will.
In some spheres, averages can be helpful to estimate various things. In a small sample it is more likely that an individual peak or trough will be visible, but in a large sample there is the distinct possibility that it can easily be overlooked if the overall average figure appears OK.
Consider a slightly different example: if PPC Analytics are showing a gradual rise in the CPA over a set period, there could be a specific reason for that result.
It may not be quite so relevant for large organisations, but for SMEs it could be a vital signal that something is not going according to plan.
The problem could be caused by new or increased competition in a specific sector, which in turn can push a budget up to its maximum limit.
Alternatively, it could mean that a specific landing page or keyword campaign is losing ground.
Remember that using only averages can easily hide a problem within PPC.
It could seem that the overall figures are fine, but looking at individual campaigns can paint an entirely different picture and clearly define where the underlying problem is.
Sometimes it is all too easy to apportion blame for a drop in traffic to major search engines' algorithmic updates, but it could equally be accounted for by the fact that Google and Microsoft both aggregate data.
The main issues that arise relate to the near-match change and the ad rotation change carried out recently by Google, leaving the webmaster unaware that a specific campaign is not going according to plan, unless he is very astute.
Even if no unusual trends are observed, PPC managers should make it part of their routine to check individual keywords and ads on a regular basis.
Pay particular attention to the worst performing keywords and make a comparison between those and the best to see if there is any obvious reason for the poor performance.