TLDR: don't inflate CPC's for absolute top of page rates, but consider performance implications of ads showing in positions 2-4 below the organic listings.
Following the additional performance metrics recently added into the Google Ads interface, we’ve analysed performance across some of our larger e-commerce clients with the view to answering the question: should we pay more for clicks to appear at the top of page 1 - above the organic listings - and not just in the top ad positions 1-4.
The new metrics include: absolute top impression % (the percentage of your impressions that are shown as the very first ad above the organic search results) and top impression share % (the percentage of your impressions that are shown anywhere above the organic search results). Let's look at these in more detail below.
Average Position 1 & Absolute Top Impression %
When an ad is shown in position 1, as the absolute top impression % share decreases, so too does the CTR of the ad despite still having an average position of 1.
This suggests that not all users scroll beyond the top of the fold results; thereby reducing the CTR of position 1 ads that are shown at the bottom of the page.
However, there doesn’t appear to be any obvious impact on conversion rates of position 1 ads when they are shown at the bottom of the page.
The question then becomes what click volume is required for profitable return; as a lower CTR means click volumes will diminish, so based on position 1 conversion rates, what level of clicks is required for maximum return.
Average Position 2-4 & Top Impression %
When an ad is shown in positions 2-4, as the top impression share % decreases, so too does the CTR; which mirrors what we’ve seen for position 1 ads.
However; unlike position 1 ads, there does appear to be a negative correlation with respect to top impression share % and conversion rate.
Similar to position 1 ads; it needs to be considered whether it is more cost effective to sit below the organic results with potentially lower CPC's and conversion rates, or above with higher CPC's and conversion rates.
When deciding on your best positioning strategy, it's also worth bearing in mind the disparity in CTR% between organic and paid traffic, by device.