How are cost center percentages calculated when the material is used in more than one work item?

This applies to the purchase invoice you create from the Work Items tab in the contract, when the project tracks costs at the work item level. In this case, each work item has its own cost center.

If the material appears in one work item, the line gets that work item’s cost center. If it appears in more than one work item with the same unit, the Cost Center column shows Multiple, and the percentage is split across the work items’ cost centers by the material quantity in each work item:

Percentage = material quantity in the work item ÷ total material quantity in the work items

Example: the material Tiles is used in Floor Tiling with a quantity of 60 and in Wall Tiling with a quantity of 40. The total is 100, so the Floor Tiling cost center appears with 60% and the Wall Tiling cost center with 40%, and the Amount for each percentage appears next to it.

The percentages appear in the form before saving, and you can edit them or add a cost center using Add Cost Center.

Note: when you convert a purchase order to a purchase invoice, the Cost Center field appears empty, so these percentages aren’t calculated automatically.