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Accounting Ver13. “Is Labor a Fixed Cost or a Variable Cost? (It Depends on the Purpose)”
Labor cost can appear variable in product costing because it is entered based on labor hours, but in investment evaluation it must be treated as a fixed cost unless headcount changes. This post explains why the distinction matters and how to structure it.

Shigenori Tanaka
5月19日読了時間: 2分


Executive Management Leadership Ver13. “How to Survive in an Inflationary Era — The Key Is Price Pass-Through, and Its Foundation Is Cost Accuracy”
Companies can no longer survive inflation without passing on rising costs.
Customers now demand precise product‑level cost breakdowns—material, labor hours, overhead, yield, and process actuals.
Only companies whose financial and managerial accounting match as “One Truth” can justify price increases.
Controllers must work on the front line with CEOs and sales, verify cost accuracy, and explain numbers directly to customers.
Survival in an inflationary era depends on accurate

Shigenori Tanaka
5月16日読了時間: 3分


Accounting Ver10. “Investment Feasibility Should Be Evaluated Using Contribution Margin — Not Gross Margin” ── Why relying on Gross Margin will always lead to wrong decisions
Many companies misjudge investment feasibility by relying on Gross Margin, which includes fixed costs and distorts returns. This article explains why Contribution Margin—based only on variable costs—is the correct metric for evaluating capacity expansion and efficiency‑improvement investments.

Shigenori Tanaka
4月22日読了時間: 3分
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