In this zone, various statistics are precomputed to then be displayed in the webapp and additional metrics are computed to create filters.

![Webapp Precomputation.png](OqafBxLnRvNQ)

 1. In the first thread going to the [activity_count](dataset:activity_count) dataset, we compute the share of traces where each activity is present. In the first grouping recipe, we group by activity and case to remove duplicates, and in the second we group by activity. As a result, we get the number of traces where each activity is present.

 2. In the second thread, we compute the performance per case, which is defined as the time elapsed between the start and the end of the case. First,  in the [grouping recipe](recipe:compute_workflow_case_performance) min and max timestamps are computed along with process time and the first attribute from the case-level columns selected by the user.



