S&OP, Demand Planning & Forecasting worked example

Demand Variability at 65% plannable demand availability: a worked example in s&op, demand planning & forecasting

Here is what the math looks like when conditions slip. We hold every other input steady and drop plannable demand availability to 65%, then walk the calculation through step by step. Estimate demand variability for sandop, demand planning and forecasting using production-ready inputs so teams can confirm whether capacity can cover demand before committing the schedule.

The inputs for this scenario

  • Demand units per planning period: 4 units / cycle (held at the documented default)
  • Planning periods in the horizon: 480 cycles (held at the documented default)
  • Plannable demand availability: 65 % (the input this scenario stresses; the baseline uses 90)
  • Clean-signal demand yield: 97 % (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Gross demand variability capacity = demand variability output per cycle × available demand variability cycles.
  • Good demand variability capacity works out to 1,211 units at these inputs, and this is the headline figure for the scenario.
  • Gross demand variability capacity works out to 1,920 units at these inputs.
  • Demand variability downtime loss works out to 672 units at these inputs.
  • Demand variability yield loss works out to 37.44 units at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where plannable demand availability sits at 90% and the headline result is 1,676 units, this scenario comes in 27.78% below the baseline at 1,211 units.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to plannable demand availability, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It scales volume with flat factors and does not compute a true statistical variance, so pair it with a coefficient-of-variation measure for buffer sizing.

Results at a glance

  • Good demand variability capacity: 1,211 units (headline result)
  • Gross demand variability capacity: 1,920 units
  • Demand variability downtime loss: 672 units
  • Demand variability yield loss: 37.44 units

Run it with your numbers

  • To rerun this with your own numbers, open the live Demand Variability calculator, set plannable demand availability to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.