Worked example

200 opening rounds + 100 added − 80 used = 220 rounds remaining in the record. A physical count is a separate check.

How the calculation works

Use nonnegative whole-round counts for one lot and period. Recorded use cannot exceed the opening quantity plus additions. A negative result is rejected instead of being presented as a valid holding.

What the result does not establish

The calculator cannot count physical holdings, establish condition, or explain a discrepancy. Keep source records and corrections dated.

Keep the connected record.

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Get Coldbore free

iOS 17 or iPadOS 17 and later. No Coldbore account.

Reviewed October 2, 2026.