The great day of third-party cookie anger has come and who can stand upright?

There was a great earthquake, the sun turned black like sackcloth, the whole moon became like blood and the stars were falling from heaven onto the earth. The heaven disappeared like a scroll being rolled up, and every mountain and island was moved out of its place.

This is the scene at the dawn of the apocalypse from the book of Revelations.

What atrocity could possibly invoke such nightmare, such havoc, and still belong on Marketing Week? Well, it’s the end of days for third-party cookies.

In truth, the stars probably aren’t going to fall out of the sky and the sun probably isn’t going to go black…but it is true that the loss of cookies is bad and it comes at a bad time.

Right now, 65% of marketing departments rely on last click attribution even though it’s acknowledged to be unreliable. The loss of cookies removes a route for fixing that and it forces already busy marketers to adapt, innovate and implement new things.

Measurement was already a mess

The chart below shows recent research on the state of measurement. It shows, on the left, that 65% of advertisers currently rely on last click attribution to optimise campaigns. On the right, the cost of that choice.

It turns out that using last click, and making sub-optimal choices about which media channels to buy, means leaving 35% of possible achievable sales  for your budget on the table.

It’s understandable. Once you start using last click, it’s sticky. Perhaps you’ve made decisions using it in the past and it would be a climb-down to change them now.

Or maybe the figures look good, like you’re performing really well. Or it’s just that the numbers are always there and changing for something else would mean less or slower access to intel.

But there’s a problem. The last click is only a small part of the purchase journey, so choosing this way limits your options.

People do a lot of research and see a lot of marketing before finally typing the name of the brand they’ve decided on into Google. Last click attribution can only see that last step, so it can never recommend earlier interventions to the purchase journey, even if they work brilliantly.

Across all advertisers in the UK and US, it’s an extraordinary waste. Some £74bn worth of sales that could have benefitted advertisers totally lost. That’s more than the GDP of Slovenia and a lot more than the entire UK defence budget. It’s a full 70 times the budget Todd Boehly has spent on new players at Chelsea since his 2022 takeover.

Infrastructure unplugged

Against this backdrop of enormous waste arising from poor measurement, this year things have got worse.

Following Apple’s decision to block third-party cookies in the Safari browser, Google has begun to do the same thing in Chrome. So far, it affects 1% of Chrome users, but it’s going to roll out to everyone in Q3 and Q4 of this year.

This matters because it renders an option that marketers previously had to improve upon last click attribution unreliable.

Without cookies, multi-touch attribution (MTA) – also sometimes called data driven attribution (DDA) – will only be able to see the last click. Where it used to be able to give credit for a sale to online touchpoints earlier in the journey, now the data on the earlier purchase journey just won’t be there.

It means that all multi-touch and data driven attribution will lurch towards a last click only view, with all the poor advice and consequent wastage that implies.

The apocalypse is here but, as with the end of the book of Revelations, a new heaven and earth are on the horizon.

Looking ahead, marketers who want to avoid messy and misleading measurement will find themselves with an attribution shaped hole in their lives.

But it would be a mistake to insist on filling that hole with something that looks and feels the same as attribution.

For many econometrics/MMM will be the answer. It can evaluate marketing that appears at any stage in the purchase journey and doesn’t need cookies. Demand has skyrocketed, with searches for econometrics/MMM in 2024 30 times bigger than they were 10 years ago (according to Google Trends data).

But econometrics/MMM done well looks and feels different to MTA or last click and, because of that, marketing people will need to use new skills and work differently.

Born in a world where data was scarce, it involves smart people with clear knowledge of how the world really works reasoning around gaps in data. Its outputs are estimates of how things work, rather counts of who does what.

This means that to do it well, you can’t just buy it once and leave it to update itself. You need to collaborate with that smart analyst to eke out its true value.

Econometrics/MMM has been modernising. As ad and media agencies have lost ground to independent providers there is now much less “marking one’s own homework”. And with ever better data and tech, good providers now offer faster turnarounds and slicker interfaces than before.

Despite all this progress, the need for reasoning and smart statisticians hasn’t gone away. Black box solutions that don’t ingest qualitative insight on how the world works often produce results that the CFO doesn’t believe. And media owners’ code – however open source – embeds a new type of “marking one’s own homework”.

Stand upright and move forward

Never waste a good crisis, because moments of change often lead to innovation when people are been willing to see them as opportunities.

The cookie apocalypse is no different. It offers up an opportunity to ditch what were already flawed forms of measurement for something much more accurate.

It offers the opportunity to bring all types of media into your measurement framework – including those that were never trackable. This opens up the possibility of doing new and better things, from influencers through to the good old fashioned telly ad.

The apocalypse is here but, as with the end of the book of Revelations, a new heaven and earth are on the horizon.

Grace Kite is the founder of Magic Numbers, which provides people-friendly analytics and practical training for marketers.