Business problem

Inventory & Working Capital

What you're holding, why it's there, and what it costs to hold it.

Metrics

Computable definitions from the KPI Dictionary — every decision switch made explicit, with the formula behind it.

KPI	Formula	What it answers
Inventory TurnsK-05	$\text{Turns} = \frac{\text{COGS}_{\text{annualized}}}{\overline{I}}, \qquad \overline{I} = \frac{1}{n}\sum_{k=1}^{n} I_k$	How many times a year does inventory turn over — with a COGS, units, or revenue numerator, an average or point-in-time denominator, and at which valuation?
Days of Supply (DOS)K-06	$\text{DOS} = \frac{\sum_{i} Q^{\mathrm{oh}}_{i}}{\sum_{i} \bar{d}_{i}}$	How long would today's stock last — against trailing history or the forward plan, in units or dollars, and what do you report when demand is zero?
Excess & Obsolete (E&O)K-10	$\begin{aligned} \text{Excess} &= \sum_{i} \max\!\left(Q^{\mathrm{oh}}_{i} - Q^{\mathrm{target}}_{i},\, 0\right) c_i \\ \text{Obsolete} &= \sum_{i \in \mathrm{Obs}} Q^{\mathrm{oh}}_{i}\, c_i \\ \text{E\&O value} &= \text{Excess} + \text{Obsolete} \end{aligned}$	How much inventory has no forward demand to justify it — and is excess defined by coverage horizon, by age, or by the accounting reserve policy?
Cash-to-Cash Cycle TimeK-11	$\begin{aligned} \text{C2C} &= \text{DIO} + \text{DSO} - \text{DPO} \\ \text{DIO} &= \frac{\overline{I}}{\text{COGS}/365}, \quad \text{DSO} = \frac{\overline{AR}}{\text{Revenue}/365}, \quad \text{DPO} = \frac{\overline{AP}}{\text{COGS}/365} \end{aligned}$	How many days is cash locked up between paying suppliers and collecting from customers — and are DIO, DSO, and DPO on consistent bases before you subtract them?

Inventory is three questions wearing one coat: how much is on hand, why it is there, and what holding it costs. Most inventory dashboards answer only the first, because the other two are authored decisions rather than sums over a ledger — which stock counts as excess, whether a reorder point is compared against on-hand or against inventory position, whether age is a mean or a distribution. The definitions here fix those choices explicitly, and the reference build runs the whole set over a frozen year of simulated daily ledger data so the arithmetic is visible rather than asserted.

Cross-ERP guides

Modeling guides that hold across every source system rather than inside one.

Inventory Snapshot PatternsThe periodic snapshot fact done right — flows as ground truth, period-end semantics, semi-additive measures, the snapshot grain decision, and late-arriving corrections.

SAP modeling guides

Start from the business question, not the table. Each guide covers the table set, the joins and their traps, the grain decision, extraction into Databricks, and working SQL.

SAPInventory & stockWhat is on hand, where, and what moved it?

Reference builds

Reference builds for this business problem, implementing the definitions above wherever one exists, running over frozen, simulated data. Not a resource and not a case study — no client data, and no client named.

In the references

Where this data lives in each source system. A way into the ERP references, not an index of them — every reference landing lists all of its modules.

SAPMaterials Management EWMStock & Handling Units JDEInventory Management D365Inventory M3Inventory & Warehouse EBSInventory

The other business problems

Demand Planning & Forecasting — How wrong the forecast is, in which direction, and where the error is worth fixing.
Customer Service & Fulfillment — Whether the order arrived complete, on the date you committed to.
Procurement & Supply — What's on order, when it lands, and how the supplier actually performs.
Manufacturing & Production — Whether the plant built what the plan said it would build.
Data Foundation & Governance — Landing ERP data in a lakehouse without losing deletes, history, or control of who reads it.

See this domain in the whole library