Mk 060

---
name: mk-060
description: "Contribution margin ratio calculation. Use when the task requires contribution amounts and revenue ratios with explicit definitions. Apply this method to the specified inputs and verify the deliverable"
---

# MK-060 | Contribution margin ratio calculation

For a regular chat, upload `packs/mk-060.md`. It includes the shared rules, this method, and required references

## Purpose

This skill delivers: **Contribution amounts and revenue ratios with explicit definitions**

Recalculability does not mean the data is complete; break-even points and cost ceilings apply only under the stated assumptions

## Required inputs

Provide: Net revenue and variable costs on the same scope, or verified contribution

For method questions, provide the formula, variables and an example directly; for a calculation, ask only for missing operands

## Method

1. Contribution margin ratio = (revenue − variable costs) ÷ revenue × 100%
2. The course material uses 30–40% as a healthy range and 25% as a floor to try not to fall below. Above 40%, also check whether variable costs have been omitted
3. These are course operating benchmarks; calculations still require the brand's actual costs

## Calculations and interpretation

Contribution margin ratio = contribution margin ÷ net revenue on the same basis

Retain original values, units, periods, and substituted formulas. The formula is not an unconditional guarantee of results

Define gross profit, contribution margin, cost denominators, and periods explicitly; do not copy classroom example numbers as universal thresholds

## Required output fields

| Order | Field | How to complete |
|---:|---|---|
| 1 | Input variable | Use source evidence, an intermediate method result, or an explicit unknown; do not invent information |
| 2 | Value | Use source evidence, an intermediate method result, or an explicit unknown; do not invent information |
| 3 | Unit and definition | Use source evidence, an intermediate method result, or an explicit unknown; do not invent information |
| 4 | Source | Use source evidence, an intermediate method result, or an explicit unknown; do not invent information |
| 5 | Formula | Use source evidence, an intermediate method result, or an explicit unknown; do not invent information |
| 6 | Result | Use source evidence, an intermediate method result, or an explicit unknown; do not invent information |
| 7 | Limitations | Use source evidence, an intermediate method result, or an explicit unknown; do not invent information |

## Verification cases

**MK-060-C05 | A required denominator is zero**

Expected: Report that the formula is undefined; do not output a zero cost or an infinite target

**MK-060-C06 | Only some costs are supplied**

Expected: Retain the partial result and excluded items; do not call it complete profitability

## Method sources

Source file: 行銷策略實戰學程Day2-以終為始x降低成本x提升指標

Location: Costs

Source basis: extracted from course materials

Source URL: https://docs.google.com/presentation/d/1NdxlcqAKMPHqGVS5jbjSYR_UgOJSA0fS65OnTtQLEHQ/edit

English translation of source excerpt:

> Begin with the end in mind x reduce costs x improve metrics