Use contribution for the decision you are making
Company-wide gross margin can hide a product that is expensive to ship, a customer that needs intensive service or a job that uses scarce machine time. Define the unit first: a unit produced, order dispatched, order delivered, billable hour or customer year. Align revenue and costs to that denominator and to the same period.
| Management layer | Example definition | Use |
|---|---|---|
| CM1 | Net realised sales less variable product or direct delivery costs. | Test product or service economics at the stated volume. |
| CM2 | CM1 less incremental selling and fulfilment costs not already deducted. | Compare channels, fulfilment methods and customer acquisition. |
| CM3 | CM2 less dedicated costs of the segment; show financing separately. | Assess recurring contribution and which costs are avoidable if the activity ends. |
CM1, CM2 and CM3 are management conventions. Define them and reconcile them to accounting results rather than treating them as statutory classifications. Use net sales excluding tax collected on behalf of government, and avoid counting discounts, rebates and refunds both as revenue deductions and as costs. Include irrecoverable input tax on the appropriate cost base where relevant. Trace direct freight and support, split mixed costs using a documented driver, and identify avoidable, committed and incremental costs separately. For statutory reporting apply the relevant accounting and cost standards, including inventory cost and abnormal waste where relevant.
Seven worked cases
1. Returns change the economics of a single-bottle order
A personal care brand charges ₹499 including GST for a 250 ml bottle. Assume it is hair oil covered by the 5% aggregate rate under the schedule effective 22 September 2025, rather than a differently classified product. The net sale is ₹475.24 and the tax portion ₹23.76. Direct materials and conversion are ₹112.50 and ₹22.80, so delivered-unit CM1 is ₹339.94.
For 100 attempts, assume 62 are cash on delivery and 32 of those fail; all 38 prepaid and 30 cash-on-delivery orders arrive. Use 68 successful orders as the denominator. Model ₹195 acquisition and ₹18.50 platform costs per successful order, a 2.36% gateway charge on ₹499 for the 38 prepaid deliveries, ₹35 collection cost for each of the 30 cash-on-delivery deliveries, ₹68 freight on every attempt, and ₹100 incremental reverse freight and damage per failed order (₹58 plus ₹42). Assume the ₹42 does not duplicate the cost of successful units. Total channel costs are ₹382.58 per delivery, leaving CM2 of about −₹42.64. Run separate channel or bundled-order scenarios before introducing prepaid discounts or a minimum basket. A change in return rate does not establish cash flow without volumes, collection dates and costs.
2. Rank production by the bottleneck
Part A sells for ₹2,400, with ₹1,420 material/tooling and ₹212 other variable costs; contribution is ₹768 (32%). Part B sells for ₹1,500 with corresponding costs ₹1,020 and ₹120; contribution is ₹360 (24%). Using 1.60 and 0.45 CNC hours per unit, contributions per constrained hour are ₹480 and ₹800.
At 7,200 usable hours and enough demand, an all-A plan makes 4,500 units and ₹34.56 lakh contribution; all-B makes 16,000 units and ₹57.60 lakh, a ₹23.04 lakh difference before other effects. With unchanged A cost, it needs a price of ₹2,912 to match ₹800 per hour; ₹2,950 gives ₹823.75 per hour. Check demand limits, commitments, changeovers and other constraints before using this single-factor ranking.
3. Put consulting revenue and labour costs on a paid-hour basis
Assume billing rates of USD 22, 55, 26 and 75 for four practices at an illustrative ₹83 per US dollar. Labour and overhead rates below are per paid hour. Compare them to billing rate multiplied by utilisation.
| Practice | Billing rate (₹ per billable hour) | Utilisation | Costs (₹ per paid hour) | Profit or loss (₹ per paid hour) |
|---|---|---|---|---|
| Legacy ERP (35 staff) | 1,826 | 88% | 1,550 | 56.88 |
| Cloud (25) | 4,565 | 91% | 3,570 | 584.15 |
| Web development (60) | 2,158 | 54% | 1,870 | −704.68 |
| Cybersecurity (20) | 6,225 | 82% | 4,470 | 634.50 |
At 160 paid hours monthly, a web engineer bills 86.4 hours. If the rates and headcount remain unchanged for a three-month quarter, the 60-person team has an illustrative fully allocated shortfall of ₹202.95 lakh. Do not treat the full allocated loss as cash savings if the practice closes. Examine scope changes, contract terms, idle capacity and redeployment.
4. Test home collection and reagent costs separately
A qualifying clinical establishment sells a ₹999 diagnostic package. Assume the services meet the health care exemption in entry 74 of Notification 12/2017–Central Tax (Rate); a wellness label alone does not decide the classification. Collection costs ₹340, reagents ₹570 (₹28 + ₹112 + ₹145 + ₹285), courier ₹65, clinical sign-off ₹50 and digital delivery ₹12. Total variable cost is ₹1,037 and CM1 is −₹38 (−3.80%).
If the ₹285 vitamin reagent component falls by 42%, it saves ₹119.70 and CM1 becomes ₹81.70 before other changes. Model a home-collection fee and alternative packages with actual incremental costs and demand; do not assume their pricing or contribution percentages from this single example.
5. Reconcile each leg of a refrigerated freight trip
Each leg is 2,150 km. At 3.2 km per litre and ₹90 per litre, diesel costs ₹60,468.75 per leg. Outbound cooling adds 8 litres per hour × 68 hours × ₹90 = ₹48,960. With tolls ₹18,400 per leg, crew and loading ₹14,500 outbound and ₹11,000 return, and maintenance ₹6,500 per leg, trip costs are ₹1,48,828.75 and ₹96,368.75. At freight of ₹1,85,000 and ₹72,000, contributions are ₹36,171.25 and −₹24,368.75, or ₹11,802.50 combined.
A separate ₹44,000 allocation for vehicle cash commitments including EMI and insurance produces a ₹32,197.50 shortfall on that cash planning basis. Loan principal is not a profit and loss expense. If return freight rises to ₹1,45,000 with identical costs, the same cash-basis result becomes ₹40,802.50; check actual refrigeration and handling costs before accepting the new work.
6. Include batch setup in the order decision
A 5,000-piece order has ₹145 fabric, ₹42 labour and ₹12 packaging per piece plus ₹15,000 setup, for ₹202 per piece. At ₹265, margin after those costs is ₹63 per piece (23.77%). A 300-piece order incurs ₹168, ₹64 and ₹15 per piece plus the same setup, or ₹297 per piece, leaving a loss of ₹32 (12.08%). With the small-run variable costs of ₹247 unchanged and ₹265 price, at least 834 pieces cover the ₹15,000 setup before other costs. Compare a setup fee, a volume minimum or outsourcing; check that cost assumptions remain valid at the proposed volume.
7. Separate customer servicing from the financing burden
A refinery customer is invoiced ₹480 lakh. Treat ₹21.50 lakh in supported deductions as a reduction to revenue for this scenario, leaving ₹458.50 lakh net. Materials cost ₹290 lakh, freight ₹38 lakh, and dedicated engineers, testing, urgent visits and packaging cost ₹28.50, ₹14.20, ₹9.80 and ₹8.40 lakh respectively. Operating contribution before finance is ₹69.60 lakh. Financing assumed average receivables of ₹225 lakh at 11.5% costs ₹25.875 lakh, leaving ₹43.725 lakh or 9.54% of net revenue.
At ₹480 lakh annual comparable credit sales, 172 days implies ₹226.19 lakh of receivables, broadly consistent with the separately observed balance. Reducing to 45 days at that same sales base would release about ₹167.01 lakh before other effects. Charging ₹3 lakh per month for engineering would add ₹36 lakh gross yearly only if contracted and earned; account for related costs and any shift in commercial terms. Check what costs disappear if the account is lost, and evaluate the alternative use of capacity.
Make the portfolio decision
Negative unit contribution calls for a prompt review of prices, returns and avoidable costs. A positive channel contribution with a negative fully allocated result can still support common overhead; model cash and capacity after an exit. Use contribution per scarce resource where one constraint binds: ₹500 over five hours is ₹100 per hour, while ₹150 over a quarter-hour is ₹600 per hour. Where several constraints bind, model them together.
Assign shared campaigns and utilities to products only with a defensible driver. Separate metered consumption from demand and capacity charges. Use supported expected yield and scrap recovery in standard costs, identify abnormal waste separately and apply the appropriate statutory costing rules. Reconcile the model to orders, invoices and accounts and confirm any available software integration before relying on it.
Sources
- MCA: Ind AS 2, including inventory cost and abnormal waste
- MCA: Ind AS 115, transaction price, returns and variable consideration
- ICMAI: CAS-3, production and operation overheads
- ICMAI: CAS-6, material cost
- ICMAI standards directory, including CAS-8, Cost of Utilities
- Notification 9/2025–Central Tax (Rate), 17 September 2025, hair oil under heading 3305 (copy of notification)
- Notification 12/2017–Central Tax (Rate), entry 74, health care services