Build an Activity Report Grouped by Day of the Week

This can be achieved by creating a custom Formula field on the Activity object and using it as a column grouping in a Matrix Report.

Step 1: Create a custom Formula field on Activity

• Navigate to Setup
• Go to Object Manager
• Select Activity
• Go to Fields & Relationships
• Click New
• Select Formula
• Give it an appropriate Field Label. The Field Name will be auto-populated based on the label
• Choose Text as the return type
• Click Next
  
  

Step 2: Enter the Formula  

• In the Formula editor, enter the following Formula

CASE( WEEKDAY( ActivityDate),1, '1. Sunday',2, '2. Monday',3, '3. Tuesday',4, '4. Wednesday',
5, '5. Thursday',6, '6. Friday',7, '7. Saturday',NULL)

• In the above Formula, ActivityDate is the date field typically used for Task
• You can replace this field with any other activity date field based on your business requirements

Note: The numeric prefix ensures that the days are sorted in the correct chronological order in the Report. Without numbering, the report will sort the days alphabetically, which can place Friday before Monday

• Click Next
• Click Next again
• Click Save

Step 3: Create the Report

• Navigate to Reports > New Report
• Select Tasks and Events Report Type
• Click Start Report

Step 4: Build The Report

• Group Rows by Assigned and Task Type/Sub-Type based on requirement
• Group columns by the new Formula field created in the previous steps
• Add Activity Type under Columns
• Enable Show Grand Totals and Sub Totals, if needed. This will display:
  • Each day of the week as a column
  • Activity counts under each day
  • Grand Total for the week
  • Breakdown by Activity Type