Name
The name of the pre-calculation. This can be entered in multiple languages (see Translation field).

Calculation
The calculation formula. It works exactly the same way as the salary type calculation, so it is not explained further here. See: Edit salary type (Calculation).

Variable
The result of the pre-calculation is stored in this variable, which can be used in the salary type calculation or in subsequent pre-calculations. The variable must start with a $ sign and must be unique across all salary types, fields, pre-calculations, sums, global values, and custom fields.

Include in sums
Just like a salary type, the result of this pre-calculation can be included in sums. See: Edit salary type (Sums).