Wearable Medical Sensors worked example

Warranty Return Reserve at 4.6% expected warranty return rate: a worked example

This scenario runs the warranty return reserve calculation on the strong side: 4.6% expected warranty return rate, with every other input held at its documented default. A finance partner setting the per-unit warranty accrual for a high-volume consumer-grade sensor launch.

The inputs for this scenario

  • Sensors Shipped Under Warranty: 50,000 units (unchanged)
  • Cost to Service a Return: 38 $ / unit (unchanged)
  • Expected Warranty Return Rate: 4.6 % (raised for this scenario; the documented default is 4)
  • Reserve Administration Charge: 3,000 $ (unchanged)

Working through the calculation

  • Applying the documented formula (Warranty reserve = units shipped x cost per return x (return rate %) + admin charge) to the inputs above produces each figure below.
  • At this operating point the engine returns 90,400 $ for total warranty return reserve cost, the number this scenario is built around.
  • At this operating point the engine returns 1.81 $ / piece for warranty return reserve cost per unit.
  • At this operating point the engine returns 87,400 $ for variable warranty return reserve cost.
  • At this operating point the engine returns 3,000 $ for fixed warranty return reserve adder.

How this compares with the baseline

  • Against the tool's baseline example, where expected warranty return rate sits at 4% and the headline result is 79,000 $, this scenario comes in 14.43% above the baseline at 90,400 $.
  • Use it at shipment recognition to book a warranty accrual, when pricing a new sensor SKU, or when field data suggests the return rate is drifting. 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

  • Total warranty return reserve cost: 90,400 $ (headline result)
  • Warranty return reserve cost per unit: 1.81 $ / piece
  • Variable warranty return reserve cost: 87,400 $
  • Fixed warranty return reserve adder: 3,000 $

Run it with your numbers

  • Every input above is editable in the live Warranty Return Reserve calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.