Industrial Equipment, Machinery & Capital Goods worked example

Machine BOM Cost Variance at 54% affected project share: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop affected project share to 54%, then walk the calculation through step by step. Estimate machine BOM cost variance from affected BOM lines, average cost variance, affected share, and fixed sourcing or engineering review cost.

The inputs for this scenario

  • Affected BOM line count: 86 lines (held at the documented default)
  • Average cost variance per BOM line: 420 $ / line (held at the documented default)
  • Affected project share: 54 % (the input this scenario stresses; the baseline uses 75)
  • Fixed sourcing and engineering review cost: 6,500 $ (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Variable machine BOM cost variance = affected BOM line count × average cost variance per BOM line × affected project share.
  • Total machine BOM cost variance works out to 26,005 $ at these inputs, and this is the headline figure for the scenario.
  • Average cost variance per BOM line works out to 302 $ / line at these inputs.
  • Variable machine BOM cost variance works out to 19,505 $ at these inputs.
  • Fixed sourcing and engineering review cost works out to 6,500 $ at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where affected project share sits at 75% and the headline result is 33,590 $, this scenario comes in 22.58% below the baseline at 26,005 $.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to affected project share, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It applies a single average variance per line, so it blurs the difference between a few high-dollar long-lead components and many low-cost fasteners; for precision, segment the BOM by spend tier first.

Results at a glance

  • Total machine BOM cost variance: 26,005 $ (headline result)
  • Average cost variance per BOM line: 302 $ / line
  • Variable machine BOM cost variance: 19,505 $
  • Fixed sourcing and engineering review cost: 6,500 $

Run it with your numbers

  • To rerun this with your own numbers, open the live Machine BOM Cost Variance calculator, set affected project share to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.