Google Analytics 4 (GA4) has replaced Universal Analytics (UA). Starting on July 1, 2024, you will lose access to Universal Analytics data in your account, the API, and in Google Ads. If you haven't completed the migration, go to the Setup Assistant to get started with Google Analytics 4.
As one of the final steps in the migration process from Universal Analytics to Google Analytics 4 properties, you’ll need to replace your Universal Analytics conversion actions with Google Analytics 4 key events. Learn more about Switching to Google Analytics 4 key events manually
You may notice discrepancies in your key event metrics because Universal Analytics and Google Analytics 4 measure key events differently. Learn more about how to increase confidence in your GA4 key event data. Switching your properties can cause short term fluctuations in campaign performance and campaign spend as Google’s bidding models adjust to the new key events.
This article helps you to understand some of those performance fluctuations and review ways to mitigate fluctuations. You can also learn more about Possible reasons for key event differences in GA4 vs. UA and how to fix your key event discrepancies.
Why you might experience performance fluctuation
After migration, you should expect fluctuation for a few key event cycles while your bid strategy adjusts to the new conversion actions (especially if the new conversion event has a different key event volume or key event delay profile).
You might notice fluctuations in your Google Ads performance in instances where:
- Your campaigns are optimized for varied conversion volumes
- You’ve recently changed your account settings
- You’ve set bidding information without considering your historical data (among other reasons)
- You’ve switched from one conversion goal to another (for example, “Booking” to “Purchases”)
How to mitigate performance fluctuation
To mitigate fluctuation, you can make these adjustments to your strategies during the transition to new key events.
Adjust your budgets
You should adjust your advertising budget in instances where your allotted spend is limited (lower than your actual average daily spend).
If you’re not sure how to determine your goal spend, refer to the following guidances:
- Budgets should be set to no more than the average daily amount you’re willing to spend (regardless of CPA or ROAS). This is important because spend can be up to 2 times your daily budget amount.
- If you’re uncomfortable spending up to 2 times your daily budget amount, reduce your budget to match your average daily spend over the last 7 days + 30% before key event migration.
Adjust your targets
In addition to budget, you can also adjust your advertising target to align with your new key event settings. To determine which targets best fit your goals, monitor your performance and adjust your targets gradually. Making target adjustments gradually helps to create a smooth transition from one target to another as old key event data is lost.
As a general practice, you should adjust targets so that they’re in line with any increase or decrease in key event volume. After you’ve adjusted your targets, continue to evaluate performance after the initial learning phase is completed, then readjust your targets to align with your business goals.
