As we do a lot of SEO work at Bloom we’re often asked to put together ROI forecasts against our SEO strategies. Inevitably this revolves around key phrase research and estimating traffic volumes that can be anticipated as rankings improve against those terms.

I thought it would be useful to share some factual observations around this based on real experience of our clients rankings on targeted key phrases and the corresponding click through rates and traffic volumes against these terms. Obviously my clients wouldn’t want this commercially sensitive information sharing with their competitors so I have had to remove the actual terms and any reference to a specific client but the data is real and hopefully of use to you next time you are trying a similar forecast.

Question 1: how does position affect click through rate? (organic position in the SERPS)

Taking a sample from a client where I have both the monthly impressions data from their PPC campaign against key phrases where they are ‘always on’ and comparing against their average organic SERPS position sampled twice weekly I was able to observe the following trends.

Unfortunately I didn’t have the position data for Jan here but we can assume that it was closer to the position regained in June. The Peak CTR achieved was around 4% against and average position of 3.8.

Here we can see a peak CTR of around 9% against an average position of 2, almost double the CTR for an average position 1.8 higher.

Here we how dropping from a top position (average of 1.75) to an average of 4.5 only a few positions lower has a dramatic affect on CTR with the peak CTR of 21.61% dropping to 5.94% with the result only 3 places lower.

Unsurprisingly the impact on traffic can be seen clearly of this drop in position.

Looking at the data I can see that where a position average of 2 was held for a month the CTR hovers around the 10% mark, where we see an average position of 1.75 held for the month meaning that for some of the month the client was at number one for the term we see the CTR double a huge difference for just one position gained for a just a proportion of the month.

Question 2: So what! this is obvious isn’t it?

Of course the fact that the higher placed you are the more traffic you get didn’t come as a revelation to me however prior to carrying out this research I hadn’t realised just how much of an impact position 1-2 makes, here we can see:

Position 1 -20% CTR
Position 2 -10% CTR
Position 3 – 6% CTR
Position 4 – 5% CTR

The drop-off is markedly slower once we pass position 3.

I do have to point out the limitations of this of course.. 3 key phrases is hardly a representative sample however without using impressions data I have verified the same degree of impact on traffic seen here from other clients gaining top organic positions. Other factors such as whether they are running PPC, how well known the brand is, what the copy under the SERP actually says etc will all have an impact.

The most important learning for me is that easing off working on key phrases once you see them hit top 5 spots to work on others is a false economy, we operate a lot of payment on results contracts with our clients and looking at this data there is a clear incentive to both the client and agency to restructure these around the very top positions, yes it’s tough to get there and perhaps even tougher to stay there, but with the right agreement this would be workable. Inevitably it would cost more but the ROI would justify the spend.