Roofing, Siding & Exterior Building Products worked example

Regional Demand Forecast at 99% in-stock service level: a worked example

This scenario runs the regional demand forecast calculation on the strong side: 99% in-stock service level, with every other input held at its documented default. Use it when regional demand forecast in roofing, siding and exterior building products is being asked to take on more work and you need to know if there is room.

The inputs for this scenario

  • Panels demanded per selling cycle: 4 units / cycle (unchanged)
  • Selling cycles in the forecast horizon: 480 cycles (unchanged)
  • In-stock service level: 99 % (raised for this scenario; the documented default is 90)
  • Order fill (non-return) rate: 97 % (unchanged)

Working through the calculation

  • Applying the documented formula (Gross regional demand forecast capacity = regional demand forecast output per cycle × available regional demand forecast cycles) to the inputs above produces each figure below.
  • At this operating point the engine returns 1,844 units for good regional demand forecast capacity, the number this scenario is built around.
  • At this operating point the engine returns 1,920 units for gross regional demand forecast capacity.
  • At this operating point the engine returns 19.2 units for regional demand forecast downtime loss.
  • At this operating point the engine returns 57.02 units for regional demand forecast yield loss.

How this compares with the baseline

  • Against the tool's baseline example, where in-stock service level sits at 90% and the headline result is 1,676 units, this scenario comes in 10% above the baseline at 1,844 units.
  • Use it when allocating production to regions, sizing regional inventory, or setting a realistic sales forecast that reflects service and returns. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Good regional demand forecast capacity: 1,844 units (headline result)
  • Gross regional demand forecast capacity: 1,920 units
  • Regional demand forecast downtime loss: 19.2 units
  • Regional demand forecast yield loss: 57.02 units

Run it with your numbers

  • Every input above is editable in the live Regional Demand Forecast calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.