Financial Planning
Gross Margin Mix: Explain Why Company Margin Moved
Separate changes inside each product’s margin from changes in the share of revenue each product contributes.
What you will learn
- calculate a revenue-weighted company margin
- build an ordered mix-versus-product-margin bridge
- reconcile percentage-point changes to gross profit
Company gross margin can fall even when each product’s own margin stays unchanged. The sales mix may have shifted toward a lower-margin product. Calculate total gross profit divided by total revenue, then separate mix changes from changes inside each product. An unweighted average of product percentages can give the wrong answer.
Keep the margin basis consistent
Use net revenue and a finance-reviewed cost-of-revenue policy for each product. Keep refunds, delivery allocations and currency treatment consistent between periods. The SEC’s financial-statement guide explains the income-statement layers; gross profit is not company net profit.
The unit-economics lesson addresses the unit cost boundary. This lesson asks what happens when product results are combined.
Work a fictional unchanged-margin example
| Product | Prior revenue | Product gross margin | Prior gross profit | Current revenue |
|---|---|---|---|---|
| A | $80,000 | 80% | $64,000 | $50,000 |
| B | $20,000 | 20% | $4,000 | $50,000 |
| Total | $100,000 | 68% company margin | $68,000 | $100,000 |
At unchanged product margins, current gross profit is $40,000 from A plus $10,000 from B, or $50,000. Company margin falls from 68% to 50% solely because the revenue mix changes. The simple average of 80% and 20% is 50%, which happened to fit the current equal-revenue mix but not the prior mix.
Add changes inside the product margins
Now suppose current product margins are 70% for A and 25% for B. At the current $50,000/$50,000 mix, gross profit becomes $35,000 plus $12,500, or $47,500.
| Ordered bridge | Company margin | Change |
|---|---|---|
| Prior mix and prior product margins | 68% | Starting point |
| Current mix, prior product margins | 50% | -18 percentage points from mix |
| Current mix, current product margins | 47.5% | -2.5 percentage points within products |
The total decrease is 20.5 percentage points, or $20,500 gross profit here because revenue stays at $100,000. Changing the bridge order changes how interaction is attributed. Disclose the chosen order and retain it.
Distinguish percentage points from percentages
A move from 68% to 47.5% is a 20.5-percentage-point decline. The relative margin-rate decline is about 30.1%. Those are different descriptions, not competing calculations. Use percentage points for the additive bridge and dollars for the profit reconciliation.
If total revenue also changes, show the revenue-level effect separately. Do not multiply a margin-point change by a different period’s revenue without explaining the basis. Keep new products and product reclassifications visible.
Copy the margin-mix worksheet
Periods, currency and product perimeter:
Finance-approved revenue and cost policy:
Product | prior revenue | prior gross profit | prior margin
Product | current revenue | current gross profit | current margin
Prior total profit / prior total revenue:
Current mix at prior product margins:
Current mix at current product margins:
Mix effect, within-product effect and interaction order:
Dollar reconciliation and rounding:
New/reclassified products and unresolved allocations:
Owner and operating question:Exercise: reject the unweighted average
Product A contributes $60,000 revenue at 60% gross margin. Product B contributes $40,000 at 30%. What is the company margin?
Answer: gross profit is $36,000 plus $12,000, or $48,000 on $100,000 revenue: 48%. The unweighted average of the product margins is 45%, which does not reflect the revenue mix.
Use the bridge to choose the next investigation
A mix shift prompts questions about demand and selling priorities. A product-level margin shift prompts questions about price, discounts, delivery cost or classification. Neither alone establishes the right product strategy.
Keep the approved mix bridge with your fundraising materials in Finta. Give Aurora the reviewed product table to help draft a plain-language account of why margin moved. Check the source calculations and ask the accountable owners to resolve allocation questions before presenting the conclusion.
Finta Field Guide. By Finta Editorial Team. Sources checked November 14, 2026. Examples are original, fictional teaching exercises, not customer results, benchmarks or individualized financial, accounting, legal or tax advice.