Methodology & Metrics
Transparency in how every metric is calculated. Every number you see in Banana Club is derived from these formulas — no black boxes, no hidden logic. Our math is auditable.
Sell-Through Rate (STR)
Data LayerWhat it measures: How efficiently inventory is being converted into revenue. A higher STR indicates strong demand alignment.
Why it matters: STR below 40% triggers governance review before replenishment. It's the primary signal for identifying slow movers and potential dead stock.
Threshold logic:
≥ 70% →
Healthy
50–69% →
Moderate
< 50% →
At Risk
SHIRT-BLU-M at Store A — Delhi NCR
Units received last season: 200
Units sold: 156
STR = (156 ÷ 200) × 100 = 78%
→ Healthy. Eligible for replenishment.
Days of Cover (Projected Coverage)
Data LayerWhat it measures: How many days current inventory will last at the current rate of sale. This is the single most important metric for triggering replenishment.
Decision trigger: When Days of Cover falls below the Dynamic Reorder Level (expressed in days), the system flags a replenishment need.
Thresholds:
≤ 1 day →
Critical (stock-out imminent)
2–3 days →
Low Stock
4–7 days →
Monitor
> 7 days →
Adequate
SHIRT-RED-M at Store B — Mumbai South
On-hand: 12, In-transit: 0, Returns:
0
Available = 12
Avg. daily velocity: 12 units/day
Coverage = 12 ÷ 12 = 1 Day
→ Critical. Immediate replenishment required.
Available Inventory (Effective Stock)
Data LayerWhat it measures: Total stock position including all sources that can fulfil demand within the planning horizon.
Key distinction: "On-hand" alone can be misleading. A store with 5 units on-hand but 50 in transit is not in crisis. Available Inventory gives the true picture.
Store A — Delhi NCR
On-hand: 30 + In-Transit: 10 + Returns:
2 + DC Stock: 150
Available = 192 units
→ Adequate. Despite low on-hand, total position
is strong.
Dynamic Reorder Level (Target Stock)
Intelligence LayerWhat it does: Calculates the inventory level at which replenishment should be triggered. Unlike static min/max, this adjusts dynamically based on changing demand and supply conditions.
Key inputs:
• Forecasted Demand — predicted units/day for the
next cycle
• Lead Time — days from order to receipt
(store-specific)
• Review Period — how often the system reassesses
(typically 1 day in Banana Club)
• Safety Buffer — grade-adjusted protection (see
#5)
SHIRT-STO-EXAMPLE at Store B (Grade A)
Forecast: 15 units/day
Lead Time: 2 days, Review Period: 1 day
Safety Buffer: 23 units (15% of forecast for Grade
A)
Target = 15 × (2 + 1) + 23 = 68 units
On-hand at 80 → Coverage OK. But predict it
crosses in 5 days.
Safety Buffer (Grade-Adjusted)
Intelligence LayerPrinciple: Higher-performing stores get deeper protection. Grade A stores serve more customers and have higher opportunity cost per stock-out.
Grade multipliers:
Grade A (Delhi, Mumbai, Gurgaon):
15% of forecast — highest protection
Grade B (Bangalore, Hyderabad, Pune):
10% of forecast — standard protection
Grade C (Nashik, smaller cities):
5% of forecast — lean buffer
Same SKU, different stores:
Forecast: 120 units
Store A (Grade A): Buffer = 120 × 15% = 18 units
Store C (Grade B): Buffer = 120 × 10% = 12 units
Store E (Grade C): Buffer = 120 × 5% = 6 units
→ Grade A gets 3× the protection of Grade C.
Open-to-Buy (OTB) Utilization
Governance LayerCapital control: OTB is the budget cap for new procurement (Purchase Orders). It protects working capital by limiting how much new inventory can be ordered.
Governance rules:
< 75% →
Healthy
— POs auto-eligible
75–90% →
Caution
— planner review recommended
> 90% →
Near limit
— only critical POs allowed
100% → Blocked — no new POs until budget reset
Monthly OTB Budget: ₹10,00,000
Used so far: ₹8,92,000
Remaining: ₹1,08,000
Utilization = (8,92,000 ÷ 10,00,000) × 100 = 89.2%
→ Caution. Next PO triggers planner review.
Forecast Accuracy
Intelligence LayerWhat it measures: How close the system's demand predictions are to actual sales. Expressed as MAPE (Mean Absolute Percentage Error) inverted for readability.
Industry benchmarks:
> 85% → Excellent for fashion retail
70–85% → Acceptable
< 70% → Needs model recalibration
Forecasted demand (last week): 120 units
Actual sales: 108 units
Error = |108 − 120| ÷ 108 = 11.1%
Accuracy = 100 − 11.1 = 88.9%
→ Excellent. Model is well-calibrated.
Store Grading Logic (A / B / C)
Governance LayerWhat it does: Classifies stores into performance tiers. Grade influences safety buffer depth, replenishment priority, and allocation depth.
Grade definitions:
Grade A — Top
20% by revenue. Tier-1 metros. High footfall. Get deepest
assortment and highest safety buffers.
Grade B — Middle
50%. Tier-2 cities. Standard allocation and buffers.
Grade C —
Bottom 30%. Smaller cities. Lean inventory, tighter controls.
Replenishment deprioritized in constrained supply scenarios.
Grade A: Delhi NCR, Mumbai South, Gurgaon
Grade B: Bangalore, Hyderabad, Kolkata, Pune,
Chennai, Chandigarh, Ahmedabad
Grade C: Nashik, Hyderabad-2
Lifecycle-Based Replenishment Control
Governance LayerPrinciple: Not every SKU should be replenished. Lifecycle stage controls how aggressively the system recommends new stock.
Stage definitions (from PDF):
Launch — New
arrivals. Conservative initial allocation. Monitor sell-through
closely.
Growth — Strong
demand trajectory. Aggressive replenishment. Maximize
availability.
Peak — Demand plateauing. Standard replenishment.
Watch for inflection point.
Decline — Sales
declining. Reduce allocation depth. Flag governance review before
any PO.
Clearance — End
of life.
Auto-replenishment completely restricted.
Recommend markdown, STO to outlet, or liquidation.
JACKET-GRY-M → Lifecycle: Clearance
System action: All replenishment requests
automatically blocked.
Governance message: "Lifecycle in Clearance — auto-replenishment
restricted."
→ Planner directed to markdown or liquidation actions
instead.
Margin & Profitability Validation
Governance LayerPrinciple: Replenishing unprofitable inventory destroys working capital. The margin filter ensures every stock movement is value-accretive.
Status definitions:
Healthy —
Margin ≥ 25%. Full replenishment eligibility.
Moderate —
Margin 15–24%. Replenishment allowed but flagged for review.
At Risk — Margin
< 15%. Governance blocks replenishment. Requires pricing review
before any stock movement.
SHIRT-RED-XL at Store G — Nashik
Contribution margin: 8% (below 15% threshold)
System action: Replenishment
blocked by governance.
Message: "Margin at 8% — below minimum threshold. Deferred until
pricing review."
→ Forces pricing correction before more capital is
deployed.