To each calculation group, add the calculation variables that you want to use:

• To define formulas.
• As scheduled unit.

Standard procedure

1.	Go to Project management and accounting > Setup > Advanced project management > Calculation groups.
2.	Click Edit.
3.	Expand the Variables section.
4.	Click Add.
5.	In the list, mark the selected row.
6.	Click Add.
7.	Click OK.
	Note: Consider filling in these fields: - Default value: You can enter a default value for a variable. If you assign the calculation group to a work breakdown structure line, its variables with the default values are added as well. - Is scheduled quantity: If this check box is selected, the variable is the scheduled unit for the calculation group. If you assign the calculation group to a work breakdown structure line, this variable is the scheduled unit for the line. For each calculation group, you can only mark one variable as the scheduled unit. - Unit: You can link a variable to a unit. This is required if you use the variable in subcontracting

Notes

• Make sure you only add the variables that you want to use. All variables, as added to a calculation group are, for example, shown in the Calculation section on the Work breakdown structure form. And it makes no sense to have unused variables shown there.
• If a calculation group is only used to define a scheduled unit, you only need to add one variable.
• If you use progress billing, mark a variable as scheduled unit. For progress billing, usually, the scheduled unit variable is a percentage.
• If you use subcontracting, mark a variable as scheduled unit, and define the unit as well. Reason: subcontracting uses purchase orders, and on the purchase lines a unit is required.