How to include time and labor hours worked in a balance

Summary:

Hi,

Our client has the following requirement for 5 elements:

Recurring element with formula : Percentage X Hourly Rate X Hours Balance

Hours Balance: includes time and labor elements only

Content (required):

Time and Labor elements do not have any input values. In order to have these elements in my balance, do we need to create an input value as 'hours' and write a logic to pass the hours, or is there a better way ?

Thank you

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