How to create a template for a fixed compensation?

Summary:

How to create a template for a fixed compensation?

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We have a group of employee that sometimes work in the evenings. They get a financial compensation for a meal. This is a fixed amount for each evening. We want them to create an expense for this. Ideally we want them to add how many days they worked late that month and have the system calculate the total based on a fixed rate? How do I set this up? They are non-consecutive days so the per diem policy doesn't work.

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