Inventory Optimizer
Overview
The Inventory Optimizer skill provides comprehensive capabilities for optimizing inventory management. It supports ABC/XYZ classification, safety stock calculation, reorder point optimization, and service level optimization.
Capabilities
- ABC/XYZ classification
- Safety stock calculation
- Reorder point optimization
- EOQ calculation
- Inventory turn analysis
- Dead stock identification
- Carrying cost analysis
- Service level optimization
Used By Processes
- LEAN-004: Kanban System Design
- CAP-003: Sales and Operations Planning
- TOC-001: Constraint Identification and Exploitation
Tools and Libraries
- Inventory management systems
- Optimization algorithms
- Demand forecasting tools
- ERP integration
Usage
skill: inventory-optimizer
inputs:
items:
- sku: "PART-001"
annual_demand: 12000
unit_cost: 25
lead_time: 5 # days
demand_variability: 0.15 # coefficient of variation
holding_cost_rate: 0.25 # annual
order_cost: 50
- sku: "PART-002"
annual_demand: 500
unit_cost: 500
lead_time: 20
demand_variability: 0.30
holding_cost_rate: 0.25
order_cost: 75
service_level_target: 0.95
analysis_type: "comprehensive"
outputs:
- abc_xyz_classification
- safety_stock_recommendations
- reorder_points
- eoq_calculations
- inventory_investment
- service_level_analysis
ABC/XYZ Classification
ABC Analysis (Value)
| Class | % of Items | % of Value | Management | |-------|------------|------------|------------| | A | 10-20% | 70-80% | Tight control | | B | 20-30% | 15-20% | Moderate control | | C | 50-70% | 5-10% | Simple control |
XYZ Analysis (Variability)
| Class | CV Range | Predictability | Approach | |-------|----------|----------------|----------| | X | 0-0.5 | High | Statistical | | Y | 0.5-1.0 | Medium | Mixed | | Z | >1.0 | Low | Manual |
Safety Stock Calculation
Safety Stock = Z x Standard Deviation x Square Root(Lead Time)
Where:
- Z = Service level factor (1.65 for 95%)
- Standard Deviation = Demand variability
- Lead Time = Replenishment time
Example:
- Daily demand: 100 units
- Daily std dev: 15 units
- Lead time: 5 days
- Service level: 95% (Z = 1.65)
Safety Stock = 1.65 x 15 x sqrt(5) = 55 units
Economic Order Quantity (EOQ)
EOQ = Square Root((2 x Annual Demand x Order Cost) / Holding Cost)
Example:
- Annual demand: 12,000 units
- Order cost: $50
- Unit cost: $25
- Holding rate: 25%
Holding cost = $25 x 0.25 = $6.25
EOQ = sqrt((2 x 12,000 x 50) / 6.25) = 438 units
Reorder Point
Reorder Point = (Average Daily Demand x Lead Time) + Safety Stock
Example:
- Daily demand: 100 units
- Lead time: 5 days
- Safety stock: 55 units
Reorder Point = (100 x 5) + 55 = 555 units
Inventory Metrics
| Metric | Formula | Target | |--------|---------|--------| | Inventory Turns | COGS / Average Inventory | Industry benchmark | | Days of Supply | Inventory / Daily Usage | Per policy | | Fill Rate | Orders filled from stock | >95% | | Carrying Cost | Average Inventory x Rate | Minimize |
Integration Points
- ERP/inventory systems
- Demand planning systems
- Warehouse management
- Procurement systems