Process cost calculator: cost per case
The cost per case is the sum over all steps: processing time times the hourly rate of the role doing it, weighted by the share of cases that pass the step, plus material cost. The steps of the invoice check worked example are filled in.
How the calculator works
The formula
Each step costs its processing time in hours times the hourly rate of the role, per pass. If only some cases pass the step, it counts with that share only. The sum over all steps plus material cost gives the cost per case; times cases per year gives the cost per year.
Why the worked example costs less here
The steps are the same as in the worked example, but without queries: every invoice is checked exactly once here. In the full example one invoice in five goes back to the supplier and is checked again afterwards, 1.25 times on average. That raises the cost from €16.13 to €17.04 per case. The lesson Branches, queries and loops shows how to include loops correctly.
What goes into the hourly rate
For a process analysis a fully loaded rate per role is usually enough: staff cost including overheads, divided by the hours actually available per year. What matters more than the second decimal place is that all roles are valued by the same rule. More in the lesson Calculating process cost.
Same calculation as the editor
The calculator turns your rows into a small process, with decisions for steps below 100%, and calculates it with the same function as the editor. Open it in the editor to add waiting times, queries or case types.
Frequently asked questions
Is waiting time included in process cost?
No. Cost comes from processing. Waiting time extends the lead time but costs no working time as long as nobody works on the case.
What counts as material cost?
Anything that occurs per case regardless of working time, such as postage, printing, fees or a license share per transaction.
How do I handle steps that happen several times?
Enter them as separate rows. For query loops that repeat a step, open the process in the editor and draw the loop; the app then calculates the average number of passes.