How do I sun total absence duration by employee?

Summary: I want to get the total days lost for each employee.

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Does anyone know how to sum in a table report that looks at the rows of data for each employee?

I want to get the total days lost by adding the duration together and have a new column showing that.

In the example below I have one employee with three absence instances and I want to add this up to show the total lost days as 3.

Thank you

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