Actual stock and theoretical stock must be compared at the same cutoff.

The short answer

This distinction changes the decision you can safely make.

Actual stock is the quantity physically counted at a stated time. Theoretical stock is the quantity calculated from confirmed inventory movements at that same cutoff. The variance is actual stock − theoretical stock; it is evidence to review, not a balance to overwrite.

Worked example

Use exact units and keep each quantity in the right category.

The system quantity is 50 pieces when the operator counts 47, so the variance is 47 − 50 = −3. A receipt of 5 pieces confirmed after the observation belongs after the cutoff. Once the −3 difference is approved and recorded, that later receipt remains intact and the current quantity becomes 52.

Decision table

Check the facts before choosing an action.

Common mistakes

Avoid shortcuts that create confusion later.

• Comparing quantities from different times
• Editing the theoretical balance to match the count
• Treating a blank count as zero
• Ignoring movements confirmed after the observation

How KnownStock handles it

The product keeps the explanation with the number.

KnownStock preserves the count scope, observation time and confirmed ledger cutoff. Review and approval create only the authorised difference as a new inventory event, while the original movements and any later activity remain visible.