Cannot find Calculated Column Option for a report

I am trying to create a calculated column in a report and there is no "calculated column" available when I edit the report.
Please advise.  My goal is to create a % of PAID-TO-DATE ( $4215) OF TOTAL LABOR COST ($6215).
This is the summary report.  Each "task" is a different record/relationship, so this is the only way I know to get the total of all tasks.


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Lynne8817 Lynne8817
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