限界利益率

The contribution margin ratio shows how much of every sales dollar is left to cover fixed costs and make a profit after paying variable costs.
The ratio is calculated by dividing the contribution margin, which is the difference between total sales and total variable costs, by total sales.
For instance, consider Prim Electronics sells gadgets worth one hundred thousand dollars.
If the total variable costs are sixty thousand dollars, the contribution margin is forty thousand dollars.
Dividing forty thousand by one hundred thousand gives a contribution margin ratio of forty percent.
This means forty cents of every sales dollar contributes to covering fixed costs and profit.
If variable costs rise to seventy thousand dollars while sales stay the same, the contribution margin drops to thirty thousand dollars, and the ratio becomes thirty percent.
A falling ratio warns managers that rising costs are reducing profits, showing the need to cut expenses or change prices.
Businesses use this ratio as a quick visual guide to compare products and evaluate pricing strategies.