Hi, I would take the following steps (might not be 100% complete but will most likely set you on the right path):

1. Create a variable with your activities, as such: ('Activity 1','Activity 2','Activity 3')
2. Create a filter on the component you wish to calculate the throughput time in as such: FILTER table.column IN <%=my_variable=>;
3. Create your component as usual to calculate throughput time.

Hope this helps! Please let us know whether you succeeded, or which concrete questions/issues you encounter.

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