##In this experiment, we test whether changing the bidding strategy from ‘Maximise Conversion Value’ to ‘Target Impression Share’ leads to improved performance in our client’s PPC campaigns.
When it comes to running PPC campaigns, choosing the right bidding strategy is key to campaign success. Whether your goal is to drive revenue with Maximise Conversion Value or increase visibility with Target Impression Share, the strategy you choose directly impacts how often and where your ads appear.
In this article, we’ll cover why testing different types of bidding strategies is essential when running PPC campaigns, how they work and look at the results of a real PPC bidding strategy experiment. In this test, we changed our client’s campaign bidding strategy from Maximise Conversion Value to Target Impression Share and measured the effect on performance.
What are PPC Bidding Strategies?
First, it’s important to understand the PPC bidding strategies we’ll be testing. PPC bidding determines which ads appear on Google’s search engine results page (SERP) and how much advertisers pay when someone clicks on their ad. Bidding strategies are the methods used to manage these bids in the ad auction to achieve specific campaign goals, such as driving conversions or increasing traffic.
Maximise Conversion Value is an automated bidding strategy that automatically sets bids to maximise the total value of conversions within your budget. This strategy is ideal for advertisers focused on maximising their ROI, rather than just high volumes of conversions.
Target Impression Share bidding is another automated bidding strategy that allows advertisers to set a target percentage of ad impressions to be shown in specific positions on the SERP. This strategy helps advertisers improve their reach, visibility and brand awareness by showing ads more frequently to potential customers.
Why run a PPC Bidding Strategy Experiment?
Google Ads experiments help advertisers conduct A/B testing on various campaign structures, settings and features within the Google Ads interface to improve their results. While keeping a clear account structure, advertisers can gain insights into what works best without risking their PPC performance and losing any budget. These data-driven experiments can help advertisers make informed decisions
Setting up our PPC Bidding Strategy Experiment
With the following Google Ads experiment, we wanted to test whether changing the bidding strategy from ‘Maximise Conversion Value’ to ‘Target Impression Share’ would lead to improved campaign performance for our client.
Impression share (IS) is the percentage of impressions that ads receive compared to the total number of impressions that ads could get. By increasing IS, we were expecting to reach and target a higher number of new potential customers by showing ads more frequently and in higher positions on the SERP.
The bid strategy of the base campaign was set to maximum conversion value with a return on ad spend (ROAS) target of 400%.
For the experiment, we changed the bid strategy of our new trial campaign to target impression share, with an IS target of 90%, and a maximum cost per click (CPC) bid limit of £1.90.
We switched on “experiment synchronisation” so that any changes to ad groups, ads and keywords of the base campaign would synchronise and apply to the trial campaign over the course of the experiment. The experiment ran for 34 days in total, with a budget/traffic split of 50%.
What we learned
At the end of the experiment, the campaigns delivered a total of 6,315 impressions, with the trial campaign accounting for 95% of those impressions, and 95% of the total £356,54 spent. Combined, the campaigns generated 384 clicks, of which 94% came from the trial campaign, however the trial CPCS were 82% higher than the base campaign.
In terms of efficiency, the trial campaign recorded a CPA of £48.59, compared to £3.29 for the base campaign. Despite these higher costs, the trial campaign drove 325% more revenue, achieving a ROAS of 158%, while the base campaign's ROAS remained stronger at 772%.
Moving to auction insights, we anticipated an increase in impression share (IS) for the trial campaign. The base campaign had previously achieved an IS of below 10%, significantly behind several competitors (Competitor 1: 34%, Competitor 2: 20% and Competitor 3: 17%). By running the experiment with a target IS of 90% and a maximum CPC bid limit of £1.90, the trial campaign achieved an IS of 32%, placing our client ahead of Competitor 1 (17%), and well above Competitors 2 & 3, both of which had an IS below 10%. The “top of page rate” also improved, rising from 56% to 89% in the trial campaign.
While the trial campaign didn’t reach the 90% IS goal, it successfully increased visibility and improved our client’s standing against their competitors. Removing the bid cap would likely have strengthened the IS performance further, though at the cost of an even higher CPA. In the long term, a higher bid cap strategy, combined with ongoing optimisations, would help balance stronger visibility with more efficient performance overall.
Key Takeaways
While the Maximum Conversion Value bid strategy is designed to prioritise conversions that deliver the highest returns, the Target Impression Share strategy focuses on achieving the specific IS goal we set for our client’s campaigns.
Increasing the IS and positioning our ads more prominently on the SERP helped raise brand visibility and reach more potential customers. Although this may not always deliver revenue as efficiently from a ROAS perspective, acquiring new customers is key to long-term business growth.
However, since IS bidding is primarily focused on awareness and reach rather than targeting the users most likely to convert, it’s expected that these campaigns will typically result in higher CPA’s and a lower ROAS overall.
Ultimately, choosing the right bidding strategy depends on your campaign objectives and business goals.
- If your goal is to expand reach and attract new customers, a Target Impression Share strategy may be the best choice. Setting realistic IS goals and maximum bid limits within your budget will help your ads appear higher and more frequently on the SERP, heightening visibility and awareness of your brand.
- If your goal is to maximise ROI efficiently, a Maximum Conversion Value strategy could be more effective. By setting a Target ROAS, you can focus on the users most likely to convert, leading to increased sales and business growth.
If you’d like to speak with one of our team about how we can help maximise your returns from your PPC campaigns, get in touch and we can have a chat about your strategy and goals.