Why Average Margin Hides Products That Lose Money

In many Swiss SMEs, revenue grows, the warehouse is full, and the income statement closes in profit — yet at quarter-end cash is tight or operating margin thins without an obvious explanation. One of the most frequent causes is results concentrated on a few profitable items, while other SKUs generate sales without covering their true costs.

SKU (Stock Keeping Unit) analysis answers a concrete question: which products or services truly contribute to profit and which erode it? Unlike an aggregated assessment by product category, the SKU level lets you link every invoice line to direct costs, commercial terms, and the operational time that item absorbs.

This guide outlines an approach suited to SMEs operating under Swiss accounting standards (GAAP/FER), with management tools such as Accountex, to turn accounting and inventory data into decisions on pricing, assortment, and commercial policy.

Essential Metrics for Every SKU

Before opening your ERP, it helps to distinguish three levels of profitability. Confusing them is the fastest way to keep catalog items that look profitable but are not.

Metric	Formula	What it reveals
Gross margin per SKU	(Net revenue − Direct cost) ÷ Net revenue	Coverage of purchase or production cost, net of discounts and returns
Contribution margin	Net revenue − Direct variable costs (material, packaging, shipping, commissions)	How much each unit sold contributes to covering fixed costs and profit
Full margin (full costing)	Contribution margin − Allocated share of fixed costs	«True» profitability after allocation of rent, indirect wages, and depreciation
Break-even point per SKU	Allocated fixed costs ÷ Unit contribution margin	Minimum volume to avoid losses on that item
Turnover and tied-up capital	Annual cost of goods sold ÷ Average inventory cost	Low values signal slow turnover and tied-up capital — typical of low-margin items

For day-to-day decisions — pricing, promotions, delisting — contribution margin is the most useful metric. Full margin is for annual strategic review and dialogue with the auditor or tax advisor, especially when evaluating investments in new product lines.

Where the Data Comes From: Accounting, Inventory, and CRM

Reliable SKU analysis requires every economic movement to be traceable down to the item code. Here are the typical sources in a Swiss SME:

Accounting data

Revenue by invoice line (net of VAT), credit notes, unconditional discounts, and direct costs recorded on material or goods expense accounts. In cost accounting, cost centers by product line facilitate allocation.

Verify that year-end adjustments — inventory write-downs, warranty provisions — are allocated by SKU or at least by product family; otherwise they distort margin in the last quarter.

Operational data

Price lists, updated purchase costs, bills of materials, picking times, defect returns, and post-sale return rates. For services, record hours per job linked to the service code.

Software such as Accountex lets you link sales and purchase invoices, inventory movements, and item master records: the goal is a single consistent SKU code across sales, purchasing, and inventory.

Five-Step Method

1

Define SKU granularity

An SKU corresponds to a distinct sellable variant: size, color, packaging, edition. Avoid aggregating too much («all cables») or fragmenting («red cable 1.83 m» if sold only by the metre). Align the definition with the code used on invoices and in inventory.

2

Calculate unit direct cost

For goods: weighted average cost (WAC) or FIFO, plus allocable procurement costs (import freight, customs duties, specific packaging). For finished products: material + direct labour + departmental overhead share. Exclude recoverable VAT: always work with net amounts.

3

Apply actual revenue and discounts

Use the price actually collected, not the list price. In Swiss B2B, volume discounts, rebates, year-end bonuses, and credit notes can turn a 35% gross margin into a negative contribution margin on small lots.

4

Allocate fixed costs with consistent criteria

Distribute rent, administration, marketing, and IT using objective drivers: machine hours, average inventory value, number of orders, revenue, or units sold. Document the allocation key: in an audit or internal control, traceability of the method is essential.

5

Classify and act

Rank SKUs by total contribution margin (not percentage alone) and cross-reference with volume and turnover. High-revenue, low-margin items deserve priority: they are often the ones that «prop up» revenue but consume production capacity and working capital.

Typical Warning Signs of Margin-Eroding SKUs

Certain patterns recur in Swiss manufacturing SMEs, distributors, and online retailers:

Signal	Possible cause	Immediate check
Positive gross margin, negative contribution	Logistics, packaging, or return costs not charged to the product	Recalculate full cost with last-mile freight and actual return rate
Growing sales, flat profit	Shift toward low-margin SKUs or structural discounts not reviewed	Month-on-month sales mix analysis for top 20 SKUs
High stock, low turnover	Bulk purchases for supplier discount that do not offset tied-up capital	Compare purchase savings with financing cost and write-downs
Small, frequent orders	Order processing cost exceeds unit margin	Calculate administrative cost per invoice line
Product «still» in catalog	Price not updated after raw material or wage increases	Compare current cost vs price locked by contract or 2023 price list

Particularities in the Swiss Context

Accounting under GAAP/FER does not require product-level reporting, but permits — and often requires for sound management — internal cost accounting. Swiss personnel costs (wages, AVS/AI/IPG, LPP, LAINF contributions) significantly affect the full margin of SMEs with local production or assembly: correctly allocating labour hours per SKU avoids overstating the profitability of automated items.

VAT (currently 8.1% standard rate) is not part of commercial margin calculation, but affects cash flow: a low-margin item with high turnover can create liquidity pressure through VAT balances, especially if customers pay in 30–60 days and suppliers require advance payment.

For import/export with the EU or third countries, verify that customs duties, clearance costs, and any currency adjustments are attributed to the correct SKU — not to a generic «ancillary expenses» account; otherwise product-level analysis remains incomplete. This is distinct from strategic currency risk management: here the goal is precise cost attribution at the time of the inventory movement.

What to Do When an SKU Is Below Threshold

Identifying an unprofitable item does not necessarily mean removing it. Evaluate levers in order of impact and reversibility:

Commercial levers

Price adjustment or introduction of minimum order quantity
Reduction of unsustainable volume discounts
Bundling with high-contribution-margin SKUs
Renegotiation of supplier terms or material substitution

Operational levers

Simplified packaging or dedicated logistics
Component standardisation across variants
Progressive delisting with customer communication
Destocking with promotion at positive contribution margin

Document every decision and monitor the effect on margins after 60–90 days. In accounting, any inventory write-downs for obsolete items should be recorded promptly, in line with the prudence principle under Swiss accounting standards (GAAP/FER) and applicable tax law — federal direct tax and cantonal/municipal profit taxes.

Automating the Analysis with Accountex

Manually repeating the analysis for hundreds of SKUs every month is fragile: coding errors, misaligned price lists, and delays in updating purchase costs render reports obsolete before they are even used. Accountex lets you maintain item records with standard cost, selling price, and analytical categories, linking invoices, credit notes, and inventory movements.

Set up periodic reports for gross margin and contribution margin per SKU, filtering by cost center, sales channel, or customer. Configure alerts on items whose purchase cost exceeds a threshold relative to list price, so you can intervene before the warehouse fills with loss-making stock.

Integrating product analysis with monthly closing gives the business owner and accountant the same numerical base — a concrete advantage in Swiss SMEs where accounting and sales often operate with separate tools.

Quarterly Checklist

☐SKU codes aligned across ERP, invoicing, and inventory
☐Purchase costs and bills of materials updated for the quarter
☐Net revenue net of discounts, returns, and credit notes for each top 30 SKU
☐Fixed cost allocation key documented and applied
☐ABC ranking by total contribution margin
☐Action plan for below-threshold SKUs with owner and deadline
☐Inventory write-down review and consistency with margin analysis