Why does data decrease with Google Consent Mode? Causes & Solutions explained

Today, privacy rules and user consent are very important. As a result, many website owners are using tools like Google Consent Mode.

This change is important for following the rules and building trust with users. However, it can lead to unexpected issues, like a clear drop in analytics data.

It is important to understand why this data drop happened. Knowing this helps us deal with the challenges it brings. This understanding is key to keeping accurate insights into how users behave.

This article will explain why data reduction occurs with Google Consent Mode. We will provide you with useful ways to enhance your analytics strategy while protecting user privacy.

Understanding data decrease with Google Consent Mode

If you recently started using Google Consent Mode and saw less data in your website’s analytics, you are not the only one.

Many website owners face this situation, especially when moving to the newer Consent Mode v2.

Although it may seem concerning initially, this decrease is normal because consent mode is designed to honor user consent related to cookies.

Why does data decrease?

Google Consent Mode adjusts how Google Analytics and other tags behave based on users’ consent preferences. When users opt out of cookies—particularly analytics and marketing cookies—Google Analytics no longer collects certain types of data, leading to a drop in your reports. Consent Mode restricts data collection for users who do not give their consent. This affects how complete your analytics data is.

The drop is often significant at the start. This is because Consent Mode only collects data once behavioral modeling in Google Analytics 4 (GA4) kicks in. This feature fills in the gaps when consent is denied by using anonymized, modeled data to estimate traffic patterns. However, there are specific thresholds that need to be met for behavioral modeling to begin compensating for the lost data:

• Your site must collect at least 1,000 events per day from users who reject analytics cookies for at least seven consecutive days.
• Additionally, there must be at least 1,000 daily users sending events with analytics consent granted during seven of the past 28 days​

For example:

• If on average 75% of your visitors to your website accept cookies in the “statistics” category.

That means that you will need at least 1.340 daily visitors (1.340 × 0,75 = 1.005) for 7 out of 28 days to model behavioral data. 

Solutions to Improve data accuracy

If you’re experiencing a drop in reported data, consider the following strategies:

1. Make use of advanced consent mode
2. Google Analytics has “built-in consent”, which means that you can allow it to load prior consent. It will adjust it’s data collection capabilities according to the consent given.
3. If you only load Google Analytics when consent has been given, no data modelling can occur.

Google Tag Manager has features that work with Cookiebot. They help you manage how tags respond to user consent choices.

Tags with built-in consent checks, like Google Ads, Analytics, Floodlight, and Conversion Linker, have logic that changes how they work. This change happens automatically based on the user’s consent state. No consent configuration is needed for this type of tags.

Google refers to this as Advanced Consent Mode.

If a tag doesn’t support built-in consent checks, you can add Additional Consent Checks for the tag as described below. If a user does not give consent to the specific consent types you’ve selected for the tag, the tag will not run. This tag will only be executed once permission has been given.

Google refers to this as Basic Consent Mode.

1. Increase Traffic: More visitors to your website can help you reach the needed numbers for GA4’s behavioral modeling. This will enhance the accuracy of your data as time goes on.
2. Leverage Behavioral Modeling: Once the thresholds are met, GA4 can use its behavioral modeling to provide more complete analytics data, minimizing the impact of the initial data loss​
3. Manual Calculations: For now, you can manually estimate total traffic based on the data collected from users who consent to cookies. This can help you approximate the total site activity​
4. Optimize Cookie Banner for Higher Opt-In Rates

Improving opt-in rates on your cookie consent banner can help minimize data loss. This will also make your analytics more accurate.

When more users consent to analytics and marketing cookies, Google Analytics can collect more complete data without relying solely on behavioral modeling. A higher opt-in rate means that less data is lost due to non-consent, leading to more reliable tracking and insights.

Use Clear, Friendly Language: Make your cookie banner simple to understand. Use simple language to explain how accepting cookies helps users. For example, cookies can improve their browsing experience. Also, explain why you collect their data

Highlight Benefits: Mention specific user benefits like personalized content or improved user experience to encourage opt-in.

Create Engaging Design: Make the banner part of the website experience. Adjust colors for your buttons in line with your normal CTA colors.

Default to Essential Cookies Only: Set a strong default that protects user privacy. Provide clear options to opt-in for analytics and marketing cookies. This could help build trust, which may lead to higher consent rates​

Conduct A/B Testing: Experiment with different banner designs, copy, and placements to see what improves opt-in rates over time.

Check out the CookieInfo Custom Cookie Banner templates for Cookiebot to get better data from your cookie banner here.

Conclusion:

In short, it’s normal for data to drop after using Google Consent Mode due to privacy rules.

To manage the transition effectively, it’s important to understand behavioral modeling and improve your website traffic. Part of this process should include enhancing your cookie banner to boost opt-in rates.

Though the drop can be disconcerting at first, with time and the right configurations, you should see the data stabilize and improve.

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