15 Sep – 4 Oct 2026 · CPA from backend orders
After a difficult run since June, efficiency in both markets improved sharply from mid-September. The US recovery was led by Google; Canada's was driven by Paid Social.
Cumulative CPA is month to date, so it resets on 1 Oct. Dashed vertical lines mark changes we made: blue is Google, purple is Paid Social.
Orders per week by channel, from GA4. The last period is 6 days, scaled to a 7-day week.
How confident we are that each change caused the result.
Weekly spend and cost per acquisition, as reported by Meta. A new campaign launched the week of 7 Sep, and budget was cut on 11 Sep.
CPA (cost per acquisition) uses backend orders and total paid media spend. Cumulative CPA is calculated month to date, so it resets on 1 Oct and early-October values rest on only a few days (for example, the one-day US spike to $91 on 1 Oct). Channel orders come from GA4, which credits the last click, so it understates Paid Social: some people who see a Paid Social ad later buy through Google or by coming direct.
Paid Social ads are currently tagged in a way GA4 files under "Organic Social". They're counted as Paid Social here. Google covers Search, Performance Max and Shopping.
Several Google changes were made on the same day, so results are credited to each round of changes rather than to individual changes.