The final lesson states the boundary: this is deterministic inventory ratio arithmetic.

highlighted = computed this step

Deterministic ratios

The calculations use fixed inventory, usage, and days-per-year inputs.

deterministic inventory ratio arithmetic\text{deterministic inventory ratio arithmetic}
What-if and scopeThe chart compares the base average inventory with the what-if average inventory.what-if and scopeturns 4; days of supply 90averageaverage 50annual usageannual usage 200what-if avgwhat-if avg 40measurevaluemeaningbeginning inventory40period startending inventory60period endaverage inventory50simple averageturns4usage / averagedays of supply90days / turnswhat-if days72lower averagedeterministic inventory ratio arithmetic only

Not forecast

This does not forecast demand or model seasonality.

outside scope: demand forecast and seasonality\text{outside scope: demand forecast and seasonality}
What-if and scopeThe chart compares the base average inventory with the what-if average inventory.what-if and scopeturns 4; days of supply 90averageaverage 50annual usageannual usage 200what-if avgwhat-if avg 40measurevaluemeaningbeginning inventory40period startending inventory60period endaverage inventory50simple averageturns4usage / averagedays of supply90days / turnswhat-if days72lower averagedeterministic inventory ratio arithmetic only

Not a promise

This does not prove cash flow, service levels, shortage risk, or causal improvement.

outside scope: cash flow, service level, shortage risk, causality\text{outside scope: cash flow, service level, shortage risk, causality}
What-if and scopeThe chart compares the base average inventory with the what-if average inventory.what-if and scopeturns 4; days of supply 90averageaverage 50annual usageannual usage 200what-if avgwhat-if avg 40measurevaluemeaningbeginning inventory40period startending inventory60period endaverage inventory50simple averageturns4usage / averagedays of supply90days / turnswhat-if days72lower averagedeterministic inventory ratio arithmetic only

Honesty note

This is deterministic inventory ratio arithmetic only. It does not forecast demand, analyze cash flow, model seasonality, promise service levels, estimate shortage risk, or prove causal improvement.

deterministic inventory ratio arithmetic only\text{deterministic inventory ratio arithmetic only}
What-if and scopeThe chart compares the base average inventory with the what-if average inventory.what-if and scopeturns 4; days of supply 90averageaverage 50annual usageannual usage 200what-if avgwhat-if avg 40measurevaluemeaningbeginning inventory40period startending inventory60period endaverage inventory50simple averageturns4usage / averagedays of supply90days / turnswhat-if days72lower averagedeterministic inventory ratio arithmetic only