At crealytics we are often asked by our clients to push various promotions within PPC ads. This blog post will investigate whether this is always a worthwhile exercise, or whether it can in fact be detrimental to performance in some cases.
When a retailer runs a promotion they are understandably keen to push the message and reach as many potential customers as possible, in the hope that the offer will drive incremental sales. Paid Search is a great place to start, as ad copy can be changed within a matter of hours and you don’t need to produce creative, aside from deciding what you want to say in the ad. Pushing offers through brand PPC ads is a really a no brainer. Generic ads however are a different story, and one thing that is often overlooked when pushing offers in ad copy for generic keywords is the impact on quality score and click costs.
For the purpose of this investigation I took data from a large fashion retailer over a period where they had a promotion live and were promoting it in non-brand ad copy. I looked at three separate ad groups over a time frame starting a week before the promotion and ending two weeks after the promotion ended. This way I can see how performance looked before and after the promotion ads were live. The first ad group contains generic keywords, the second and third contain designer keywords. In all three I have compared the click-through-rate (CTR) and cost-per-click (CPC) of the promotion ad, at least one standard ad, and the overall performance of the ad group.
Here are the results.
Ad Group 1 (generic keywords): CPC increased, standard ad performed better than promo ad
The two graphs above show the findings for Ad Group 1. The CTR and CPC trend is split for the three different ad copy variations and the ad group overall. We can see that the ad with the highest CTR throughout the whole period was Standard Ad 2, which was 10% higher on average than Standard Ad 1. The Promo Ads performance the weakest, but not by much.
When we look at the CPC trend we can see that all ad variations saw a significant increase once the promotion started. The overall CPC for the ad group increased by 264% in the first week. Keyword bids were increased slightly during this time and bid adjustment were made for RLSA lists, which will have had some influence on these numbers. Even taking those factors into account we would not expect such a significant increase, so the addition of the new ad copy is likely be a major factor driving up CPC.
Ad Group 2 (designer keywords): CPC increased, promo ad performed slightly better than standard ad
In Ad Group 2 the average CTR of the promo ad was 20% higher than that of the standard ad. As this ad group is set to automatically optimise for clicks the promo ad served more impressions than the standard ad, which is the reason for the close correlation between the promo ad and the overall.
Again, CPC increased significantly when the promo ad was first activated. Overall CPC for the ad group increased by 183% in the first week. CPC reduced quicker in this Ad Group 2 than in Ad Group 1, which was likely to be due to the Promo Ad’s higher CTR.
Ad Group 3 (designer keywords): CPC increased, promo ad performed better than standard ad
In Ad Group 3 the CTR of the Promo Ad was only slightly higher than Standard Ad 1, despite being much higher in the first couple of days.
As with the other two Ad Groups, CPC increased when the Promo Ad was activated, albeit less severely. Overall CPC increased by around 40% in the first week. The initial spike in CTR when the promo ad was activated could have helped to limit the increase in CPC.
Clearly there is a short-term negative impact on performance when activating new ad copy. This must be taken into account when deciding whether to promote offers in non-brand ad copy. A strong offer will always generate plenty of interest, but for short-term and less impactful promotions you could be better off from a performance perspective not to promote the offer in PPC ad copy and allow the user discover the offer once they reach your site.
Another thing to keep in mind when re-writing ad copy to mention a promotion, is that something needs to be left out to make space. So the question must be asked; has the ad become less relevant to the keyword and landing page as a result of this change? If the answer is yes, then the ad may have weaker performance than the existing, more relevant ads. Again, the strength of the promotion will be a big factor here.