Why 1+1 Doesn’t Equal 2: A Guide to Attribution

Where are our sales coming from?

We’re often asked by clients about why 1+1 doesn’t always equal 2 and although we’d love to give a simple answer, the reality is that conversion attribution isn’t always a simple sum. Here Jaye, tries to explain why!

Client: “In August Google Analytics is reporting revenue from social as £5521.71, whereas Shopify is reporting it at £3357.75, which is right?

Launch Account Manager: “Are you sitting comfortably, then I’ll begin…”

Firstly it is really important to remember that you can’t track every sale, there are too many buying decisions which can’t be reflected in data, so all reporting is giving you an indication of the sales which can be tracked but not 100% of your sales.

The path to purchase is often not one visit to the website = one sale, it is likely that the user visits the website several times, on several devices and might even have an offline interaction, recommendation, press article etc. Therefore website conversion reporting is not simple and when you add into this equation that each platform uses different ways of tracking these sales.

Last Click Attribution

Most reports track ‘Last Click’ and attribute the purchase to the last channel that sent the user to your website before the purchase was made but this excludes the impact of the other channels which contributed to that sale.

For example, user searches “wooden toys to buy online”, clicks on Google Ads, comes to website, finds something they like but wants to see if it is cheaper elsewhere. Goes back to Google and searches for the product name, shopping results come up, they see you offer the best price, they click on your shopping ad, come to the website and then get distracted by child swallowing marble in lounge.

Later when they are in bed with wine and a biscuit, they scroll through Facebook, like a picture of their friends ugly baby and then see your Facebook Ad, remember they haven’t bought Jonny’s sustainable wooden tractor, click on the ad and then buy it.


Michael Bergmann

Shopify and Facebook will credit Facebook for that sale (if the user wasn’t in private browsing mode in Safari…but that’s another story – Google ITP 2.0) and yet two Google campaigns contributed to this sale and were responsible for the user finding your brand in the first place – which will only show up in the Google Analytics multi channel funnels report.

Top Conversion Paths

The reports we give clients normally come from GA top conversion paths which attribute the sale to the channel whether or not it was the only channel used.

This gives a better indication of the value of that channel. Obviously there are numerous sales which can’t be wholly tracked, especially when mobile is involved as users might not be signed in and therefore reporting is only an indication of the value from a particular campaign.

Here is an article which probably explains it better than I can > Ruler Analytics Click Attribution In addition to the above, each channel uses slightly different code/method to track a sale – Facebook tends to over report as it also credits a sale where there is an impression “The default Facebook attribution window settings show actions taken within 1 day of viewing your ad and within 28 days of clicking your ad.” whereas Shopify will be last click only and Google Analytics is last click in some reports except the Multi channel funnel report.

On top of all of this, recent changes to IOS devices using safari (ITP2.0) mean that tracking from mobiles has got harder so we can’t track the campaigns as accurately as before and GDPR has also had an impact with cookie prevention and ad blocking software.

Are you still there?

Hutomo Abrianto

We hope this explains why the figures don’t always tally, it’s a constant challenge for our industry and just as things were getting better, GDPR came to complicate things. The word on the virtual street is that one day, tracking will be impossible because of user privacy, so enjoy the flawed reports as soon we might not have any reporting.