Fair-Share Allocation Formula
How apparel allocators distribute a buy across doors using proportional demand — and when to override for floor-set and size-curve needs.
What Fair-Share Allocation measures
Fair-share allocation distributes a total buy across doors in proportion to demand. It is the baseline allocation math before overrides for floor-set minimums, protected doors, or experimentation.
Door Units = Total Allocation × (Door Demand ÷ Chain Demand)Worked apparel example
5,000 units to allocate across a chain. This door's demand signal is 450 units against a chain total of 3,800.
Door Units = 5,000 × (450 ÷ 3,800) = 592 units
Pure fair-share says 592. Then overrides kick in: floor-set minimum might push it to 600; protected A-door status might push to 650; cluster downgrade might pull to 500.
Door gets 592 units on a pure fair-share basis. Override for floor-set minimums, size-curve needs, or protected doors.
When to override fair-share
| Reason | Typical adjustment | |---|---| | Floor-set display minimum | Round up to display pack | | Protected A-door | +5–10% | | Cluster downgrade (size range pulls) | −10–20% | | New-launch hold-back | Keep 20–30% in DC for chase | | Size-curve gap | Rebalance sizes but hold total |
Failure modes we see
Fair-share applied mechanically, no size-curve check. A door gets 592 units on fair-share. But the size-curve application lands 180 units in size S at a door whose customer base is heavier. The floor set opens missing mediums and overstocked on smalls.
How RetailNorthstar handles fair-share allocation
Fair-share is the starting point; the system layers override rules by cluster, floor-set calendar, and door economics. Size-curve overlap is checked before the ship plan is finalized.
Related formulas
- Door-Level Demand Index — the demand input
- Size Curve Allocation — the size overlay
- Replenishment Trigger — what happens after initial allocation
See fair-share allocation with rules-based overrides layered transparently — not hidden in spreadsheet formulas.
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