Supply Chain & Procurement worked example

Resilience Buffer Calculator with inventory on hand of 2,300 units: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop inventory on hand to 2,300 units, then walk the calculation through step by step. Estimate protected supply days from buffer stock, daily demand, and risk factor.

The inputs for this scenario

  • Inventory on hand: 2,300 units (the input this scenario stresses; the baseline uses 4,500)
  • Average daily consumption: 300 units / day (held at the documented default)
  • Disruption safety multiplier: 1.2 x (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Protected days = inventory on hand ÷ daily usage ÷ safety multiplier.
  • Protected days of supply works out to 6.39 days at these inputs, and this is the headline figure for the scenario.
  • Unprotected days works out to 7.67 days at these inputs.
  • Inventory works out to 2,300 pieces at these inputs.
  • Daily usage works out to 300 pieces / day at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where inventory on hand sits at 4,500 units and the headline result is 12.5 days, this scenario comes in 48.89% below the baseline at 6.39 days.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to inventory on hand, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It assumes steady daily usage; if demand is lumpy or seasonal, protected days can be overstated because a single high-consumption day burns buffer faster than the average implies.

Results at a glance

  • Protected days of supply: 6.39 days (headline result)
  • Unprotected days: 7.67 days
  • Inventory: 2,300 pieces
  • Daily usage: 300 pieces / day

Run it with your numbers

  • To rerun this with your own numbers, open the live Resilience Buffer Calculator calculator, set inventory on hand to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.