Google SERP Changes & Ad Performance: Expectations & Reality

by Tom Manning on Wednesday 13 April 2016

What happened?


On 22nd February Google rolled out changes to remove the ads from the right hand side of the search engine results pages on desktop. It made this change on mobile and tablet in 2011 and has stated this will now bring parity across all devices. As part of the change Google may now also show four ads at the top of certain queries across all devices for what it refers to as ‘highly commercial’ queries. Google Shopping results will still be eligible to appear on the right hand side as they currently do.


How can we monitor changes?


Prior to the 2011 change Google used to provide data to show when ads were appearing on the top or the side of the page, which was very useful for bid optimisation. However, it has since changed the data to ‘Top vs. Other’ where ‘other’ refers to either the bottom or the side of the page. This means you cannot get data on performance changes between the side and bottom of the page to make a true comparison.


However, we can at least look for some impact before and after the change on how ads displayed on the side and bottom compare to ads that are now just on the bottom of the page and again, how that compares to ads on the top.

To analyse this at scale across all of our clients we have separated brand and non-brand traffic and removed search partners (ie. Ads not served on Google’s own search results) in order to get a clean read on the data. We also split out Google Shopping (Product Listing Ads) results for reasons that are covered later.

It is an option to track every position an ad was served for each click using a ValueTrack Parameter within AdWords, but this unfortunately can’t be applied retrospectively. Competitor monitoring tools may also have raw SERP level data, but it is worth noting this is based on scrapes of the SERPs that may only happened daily or hourly. Given the customization Google gives to SERPS and how much it can vary auction by auction this is only ever going to be a broad steer on the most stable SERPs.

What did we expect to see?

Based on our own predictions and thoughts people have shared in other posts, we have constructed a list of the most common expected changes, relating it back to what we would expect to see in the ‘Top vs. Other’ reports we are using for analysis.

1.   Reduced CTRs for Other

Many people feel bottom of the page click through rates (CTRs) are lower than the side, therefore serving these ads at the bottom of the page instead of the right will mean the ‘Other’ segment of the report will see reduced CTRs. It is worth noting that Google disagrees with this viewpoint and has stated that it measures better CTRs at the bottom of the page than on the side and are using this to justify the change.

2.   Increased average CPCs for top of the page ads


If ads do perform worse at the bottom of the page, then this may force people to increase bids in order to appear at the top of the page instead. It is also expected that with more ad slots available for certain queries, this may increase competition for the 4th position which in turn, would increase average CPCs for ads above that. 4 ads are only expected to be shown for a smaller number of queries so the impact from this may not be seen on overall data.

3.   Drop in traffic for ‘Other’

Along with people predicting a lower CTR for bottom of the page ads compared to the side, logically we would expect to see fewer impressions overall for ‘Other’. The reason being there could be up to 8 ads on the side of the page and with 3 on the top that takes the maximum total number of ads served to 11. With the changes, there are a maximum of 4 ads on the top and 3 on the bottom of the page meaning just 7 ads can show. This means anyone below position 7 would not show on the front page and expect to see fewer impressions.

4.   More Google Shopping results shown

It is widely believed that with the right hand side now being free of text ads, it will page the way for more Google Shopping results, which can still show on the right.

5.   A knee-jerk reaction to the changes

As with any big change (the last major one being Enhanced Campaigns), there is often reactionary panic that could lead to short-term aggressive strategies as people try to anticipate the changes and preempt any impact from them. This knee jerk reaction could cause immediate changes in metrics (typically average CPC) but they would likely settle down over time.

6.   Reduced CTRs for top ads

As there are some SERPs showing 4 ads at the top of the page, this increased competition is expected to lower CTRs for those top ads, simply because there are more options for the user. However, given that position 4 is simply pushing down the first natural search result, it may not have any impact at all on the top results.

7.   Decline in average positions for top ads


Although not a common opinion, it is logical to expect that because position 4 now could count as ‘Top’ as opposed to only positions 1-3 previously, the average position for ‘Top’ as a group should drop.


What does our data actually show?


To find out what the data from across our accounts seems to indicate, please complete the form below: