Google Ads to move from Last Click to Data Driven Attribution

Google has announced it is switching from Last Click attribution on Google Ads to Data Driven Attribution (DDA).

In a sense this is surprising, because bottom of the funnel activity like paid search – and especially brand search – does really well against a Last Click model.  However, Data Driven Attribution should deliver a more nuanced and holistic view of how different Google Ads campaigns are driving value. For instance, generics campaigns might be undervalued versus brand, assuming generic searches are part of a multi-visit journey.

When is this happening?

The roll out is starting in October 2021 and will be complete by year end.

Oh no. I love Last Click attribution and can’t live without it.

Whisper it quietly, but Last Click gives decent results for use cases where there isn’t a long consideration cycle.

Anyway, don’t panic – whilst Data Driven Attribution is becoming the default, you can still manually switch back to Last Click, First Click, Linear, Time Decay and Position-based models.

Why are Google doing this?

Partly because Data-driven attribution can deliver better results for advertisers. For instance, Lara Harter, Head of Online Marketing at DocMorris claims an 18% reduction in the cost of sales after switching from last-click attribution.

The other reason though is as a response to privacy concerns. It is likely that some journeys are not being effectively tracked because  cookies from earlier touchpoints have been deleted by the time of the conversion, so they’re not fed back to Google Ads.  DDA uses real conversion data enriched with machine learning techniques to build a more complete view of where value is being created. Potentially it can help advertisers to make better decisions with more limited data.

Doesn’t Data Driven Attribution need a lot of data?

That was the case in the past.  Deploying DDA in the past took a long training period to create a custom attribution model.

Google seem to have solved that problem, and feel confident that their algorithms can deliver a sound model even for low-traffic domains.

Again, if you don’t like the results you are seeing from DDA, you or your agency can manually switch back to Last Click.

What about Google Analytics?

Right now, Last Click remains the default within Google Analytics. Assuming that there is a cost to Google in deploying DDA, our bet will be that DDA will remain an option in GA rather than becoming the default.

Advertisers though are bound to want a consistent way to measure across different channels, so if they accept DDA for Google Ads we can see it becoming a common choice in Google Analytics.