Attack scrap and rework at the source
When it may fit: Waste per unit is rising.
Evidence needed: Defect data by product, line and cause.
Trade-off: Quality fixes need engineering time.
Manufacturing Intelligence Brief
How to Investigate Rising Unit Costs
Cost per unit is the plant’s basic efficiency measure. When it rises, breaking it into materials, labor, overhead and scrap shows which part is responsible.
1. The business problem
Each unit costs more to make than last year. Which part of the cost is to blame?
Total cost rises with volume, which is normal. Cost per unit rises when something gets less efficient or more expensive: materials prices, labor productivity, spreading of overhead, or waste.
A cost-per-unit breakdown by component shows where the increase sits, and which part deserves attention.
2. What the evidence can reveal
A unit-cost investigation uses a simple decomposition:
- Calculated Materials, direct labor, overhead and scrap and rework, each divided by units produced.
- Calculated Change in each component from the prior period, in dollars per unit.
- Calculated The effect of volume: overhead per unit usually falls as volume rises.
- Information gap Reasons behind each change: supplier prices, wage rates, yield, downtime and product mix.
The component that grew most in dollars per unit is usually the place to start.
3. Investigate the problem
In the synthetic plant, Calculated cost per unit rose from $34.23 to $35.08, up 2.5%, on units produced up 8.8%. Operating margin fell from 16.2% to 13.3%.
Calculated Dividing each cost line by units gives the pattern. Materials per unit rose from about $17.32 to about $17.67 (up roughly 2%), direct labor from about $8.38 to $8.54, and overhead per unit fell slightly, from about $6.90 to $6.86, as volume spread it. Scrap and rework per unit rose from about $1.62 to $2.01, up roughly 24%, the largest rise of any component, and the biggest single contributor to the increase of about 85 cents.
Hypothesis Scrap and rework is the clearest problem, with downtime (35.5% more hours) a likely related factor. Information gap The demo does not say which lines or products the scrap comes from, or why. In the scenario, a 1% change in materials cost per unit is worth about $273K, while a 1% change in scrap and rework cost is worth about $31K, but scrap grew 34.8%, so the dollars are larger than a 1% change suggests.
4. Explore the interactive experience
Investigate it yourself.
Manufacturing Performance Dashboard: a product-line dashboard with downtime and scrap, a scenario simulator for volume, price, materials and scrap, evidence-linked answers from APIS, and a sample brief, all on synthetic data.
The experience below is built on a synthetic manufacturer, “Demo Components Inc.,” analyzed by product line. It has no station-level, machine-level or line-level records, so product lines are used to show the method. Nothing in it is real.
- In the cost table, select Scrap & rework and compare its growth with units produced.
- Then select Materials. Which grew faster per unit?
- Ask APIS why higher production volume does not always improve profitability.
5. Evaluate possible solutions
The right response follows the component that grew.
6. What leadership should do next
Questions to answer
- Which cost component grew most per unit?
- Is the increase price, usage or waste?
- Which products are affected?
- What is it worth to fix?
Data to gather
- Cost by component per unit
- Scrap and rework by cause
- Supplier prices
- Labor hours per unit
Steps to take
- Decompose unit cost.
- Rank components by increase.
- Investigate the largest.
- Re-measure monthly.
7. Engage Two Pillars
Identify Opportunities Across Production, Costs, and Capacity
Two Pillars can help manufacturers investigate production performance, cost structure, inventory and capital investment decisions using your own plant data. A good first step is a unit-cost decomposition that ties each component to a cause and a dollar value.
Sources and data notes
- The organization, its figures, and every number in this article and its interactive experience are synthetic and illustrative. They are not real data, a benchmark, or a forecast.
- Reviewed October 2026. This article describes an approach to investigation. It does not replace review by qualified professionals.