Retail Sell-through Planner methodology

availableUnits = beginning units + units received

sellThroughRate = units sold / available units

remainingUnits = available units − units sold

remainingInventoryCostExTax = remaining units × unit cost

salesRevenueExTax = units sold × selling price per unit

grossMarginExTax = units sold × (selling price − unit cost)

targetSoldUnits = available units × target sell-through rate

additionalUnitsToTarget = maximum of zero and target units less sold units

observedUnitsPerDay = units sold / elapsed days

Money inputs and outputs use the currency selected in the scenario without changing the canonical methodology. Rates, margins, utilisation and buffers are entered as percentages and converted to decimal values for calculation.

• All inputs must be finite and remain inside the visible validation boundaries.
• Whole-unit and whole-day fields reject fractional values.
• Percentages remain inside the closed range from 0% to 100%.
• Invalid denominators return an explicit unavailable result or fail closed; NaN and Infinity are never displayed.
• Units sold cannot exceed beginning units plus units received.
• Unit cost cannot exceed selling price when gross margin is presented.

Beginning units minimum

beginningUnits ≥ 0 whole units/cohort period — A lower value is rejected before calculation.

Beginning units maximum

beginningUnits ≤ 100,000,000 whole units/cohort period — A higher value is rejected before calculation.

Units received minimum

unitsReceived ≥ 0 whole units/cohort period — A lower value is rejected before calculation.

Units received maximum

unitsReceived ≤ 100,000,000 whole units/cohort period — A higher value is rejected before calculation.

Units sold minimum

unitsSold ≥ 0 whole units/cohort period — A lower value is rejected before calculation.

Units sold maximum

unitsSold ≤ 100,000,000 whole units/cohort period — A higher value is rejected before calculation.

Selling price per unit minimum

sellingPricePerUnitExTax ≥ 0 currency units/unit, ex tax — A lower value is rejected before calculation.

Selling price per unit maximum

sellingPricePerUnitExTax ≤ 10,000,000 currency units/unit, ex tax — A higher value is rejected before calculation.

Unit cost minimum

unitCostExTax ≥ 0 currency units/unit, ex tax — A lower value is rejected before calculation.

Unit cost maximum

unitCostExTax ≤ 10,000,000 currency units/unit, ex tax — A higher value is rejected before calculation.

Elapsed days minimum

elapsedDays ≥ 1 whole elapsed days/cohort period — A lower value is rejected before calculation.

Elapsed days maximum

elapsedDays ≤ 100,000 whole elapsed days/cohort period — A higher value is rejected before calculation.

Target sell-through rate minimum

targetSellThroughRate ≥ 0 decimal fraction of available cohort units sold — A lower value is rejected before calculation.

Target sell-through rate maximum

targetSellThroughRate ≤ 1 decimal fraction of available cohort units sold — A higher value is rejected before calculation.

• All inventory, sales, cost, target, capacity and cash values are supplied by the user.
• Money inputs use one consistent ex-tax currency basis and records refer to the same cohort or planning period.
• The engine retains raw precision; display formatting never feeds back into calculation.
• No jurisdiction, provider fee, industry benchmark or current policy value is embedded.

This planner has no current policy-data dependency. Its commercial assumptions are user supplied. Registered family-level regression suites exercise the shared business-logic engine and worked-result reconciliation.

• The received cohort and target are user-defined and must cover one consistent observation period.
• Observed units per day describes the entered history; it is not a future sales forecast.
• The model excludes returns, transfers, shrinkage and price-mix changes unless reflected in the records.

This is educational decision support, not tax, accounting, legal or financial advice. Check the treatment of your actual transactions under the rules that apply to your business and seek qualified advice where appropriate.

Registered family-level suites test formula invariants and example reconciliation; the release ledger records that coverage without claiming a separate oracle for every line of public copy. There is no official threshold or benchmark to refresh for this planner. Commercial inputs remain user-supplied because they vary by business and contract.

1. 2026-07-16: Initial public release of the Retail Sell-through planner and methodology.