Manufacturing Fixed Costs to Sales: A Semiconductor Benchmark Framework
No universal appropriate ratio
A blanket 20% or 30% target is misleading without specifying the manufacturing model and cost definition. Fabless companies pay supplier prices containing factory costs, while IDMs and foundries carry those costs directly. New fabs incur substantial depreciation; a fully depreciated legacy fab can show a lower ratio without being more productive.
Utilization, selling prices, product mix, technology, and asset age all influence the ratio. TSMC’s 2024 reporting links gross-margin improvement to capacity utilization and productivity. Define the numerator consistently: factory depreciation, fixed labor, maintenance, and facility overhead; exclude R&D and selling expenses.
Derive the limit from required economics
Maximum manufacturing fixed costs / sales = 100% minus variable manufacturing cost ratio minus target gross margin. This identity assumes manufacturing costs are fully and consistently divided into fixed and variable categories.
For example, variable manufacturing costs of 35% and a required gross margin of 45% leave a 20% fixed-cost allowance. This is an illustrative planning limit, not an observed industry standard. Gross profit must fund R&D, administration, and operating profit; the business must also earn adequate returns on invested capital.
Normalize and stress-test
Set targets using sustainable selling prices and normal utilization, then stress-test downturns. Separate cash factory fixed costs from depreciation, and compare peers with similar technology and manufacturing models. A falling ratio caused by price increases is not the same operational improvement as removing a redundant cost block.