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Retail math · By role

Retail Math for Buyers in Apparel

Buy quantity, average unit cost, PO coverage, and size-curve math every apparel buyer uses from line review to PO issue.

15 formulas for buyers
InventoryAlso: Planner
Open-to-Buy (OTB)
OTB = Planned Sales + Planned EOP + Planned Markdowns − Planned BOP − Receipts on Order
MarginAlso: Merchandiser
Initial Markup % (IMU)
IMU % = (Retail Price − Cost) ÷ Retail Price × 100
ProductivityAlso: Analytics
Sell-Through Rate
Sell-Through % = Units Sold ÷ Units Received × 100
InventoryAlso: Planner
Weeks of Supply (WOS)
WOS = On-Hand Units ÷ Average Weekly Unit Sales
InventoryAlso: Allocator
Fill Rate
Fill Rate % = Units Shipped ÷ Units Ordered × 100
MarginAlso: Designer / Product Dev
Target Costing
Target Cost = Retail Price × (1 − Target IMU %)
MarginAlso: Designer / Product Dev
Cost-to-Ticket Ratio
Cost-to-Ticket = Cost ÷ Retail Price
InventoryAlso: Designer / Product Dev
Style-Color Depth
Units per Style-Color = Total Buy Units ÷ (Styles × Colors)
InventoryAlso: Planner
Stock-to-Sales Ratio (SSR)
SSR = Beginning-of-Period Inventory ÷ Sales for Period
InventoryAlso: Planner
Receipt Plan
Receipts = Sales + EOP + Markdowns − BOP
Sales
Average Unit Cost (AUC)
AUC = COGS ÷ Units Sold (or Inventory at Cost ÷ Units On Hand)
SalesAlso: Analytics
Average Unit Retail (AUR)
AUR = Net Sales ÷ Units Sold
Inventory
Buy Quantity (Units)
Buy Units = (Sales Forecast Units + EOP Target − BOP) ÷ (1 − Expected Markdown %)
Inventory
PO Coverage %
PO Coverage % = Units on Order ÷ Units Needed × 100
Inventory
Size Curve Allocation
Units per Size = Total Buy × Size % from Curve
Buyer Cheatsheet

Retail Math Cheatsheet for Buyers

A role-specific PDF with the formulas buyers use day-to-day — equations, worked apparel examples, and the adjacent formulas you work with. Work email only — no sales calls triggered.

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Other roles
Designer / Product Dev →Merchandiser →Planner →Allocator →Supply Chain / Ops →Analytics →Executive →All formulas →
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