Google Analytics 4 (GA4) has recently unveiled a significant update to its API, introducing a new sampling level feature in the reportTasks method. This enhancement offers users greater control over data sampling in their analytics reports, particularly benefiting Google Analytics 360 properties.

Key Features of the Update:

1. Sampling Level Control: Users can now adjust the sampling level using the samplingLevel field in the properties.runReportTask method.

2. Increased Sampling Limits: Google Analytics 360 properties gain access to higher sampling limits of up to 1 billion events.

3. Unsampled Results Option: The ability to set sampling limits to UNSAMPLED for large event count unsampled results.

Sampling Level Categories:

The API update introduces four sampling level categories:

1. SAMPLING_LEVEL_UNSPECIFIED: Default unspecified type.
2. LOW: Applies a 10 million event sampling level to standard properties and 100 million to Google Analytics 360 properties.
3. MEDIUM: Exclusive to Google Analytics 360 properties, offering a 1 billion event sampling level.
4. UNSAMPLED: Also exclusive to Google Analytics 360 properties, providing unsampled explorations for more accurate insights.

Data sampling in analytics involves analyzing a subset of data to extract meaningful information from larger datasets. This practice allows for quicker data retrieval while maintaining data quality. In GA4, sampling occurs when the number of events exceeds the quota limit for a property.

When sampling is applied, GA4 indicates this through a data quality icon, showing the percentage of data used. A higher sample size generally correlates with more accurate results.

Conclusion:

This GA4 API update offers users more granular control over their data analysis, potentially leading to more accurate and insightful reporting. For businesses relying on detailed analytics, especially those using Google Analytics 360, this feature provides a valuable tool for deeper data exploration and decision-making.