MK-074 | Marketing return on investment calculation
For a regular chat, upload packs/mk-074.md. It includes the shared rules, this method, and required references
Purpose
This skill delivers: An mROI calculation with explicit definitions and cost boundaries
Recalculability does not mean the data is complete; break-even points and cost ceilings apply only under the stated assumptions
Required inputs
Provide: Revenue, gross margin rate or costs, marketing expense and the ROI definition for the same analysis scope
For method questions, provide the formula, variables and an example directly; for a calculation, ask only for missing operands
Method
- The course mROI formula: [(revenue × gross margin ratio) − marketing expense] ÷ marketing expense × 100%
- Use the same analysis scope for revenue, gross margin ratio, and marketing expense; do not force the calculation when marketing expense is zero
- Use mROI to assess financial accountability; it does not replace process diagnosis of traffic, conversion, average order value, and related metrics
Calculations and interpretation
Calculate using the ROI definition specified for this case. If none is specified, present advertising ROAS alongside available cost items; do not independently call revenue divided by spend a profit ROI
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-074-C05 | A required denominator is zero
Expected: Report that the formula is undefined; do not output a zero cost or an infinite target
MK-074-C06 | Only some costs are supplied
Expected: Retain the partial result and excluded items; do not call it complete profitability
Method sources
Source file: 營業額提升主要關鍵（三）從數據來提升 ROI 的策略
Location: mROI
Source basis: extracted from course materials
Source URL: https://docs.google.com/presentation/d/1lwpCxF1cMgaK7Gnvngw8NzytDLYD8MK-p91g8dwSytU/edit
English translation of source excerpt:
mROI =
