In process costing, an expected material loss inherent to the production process is termed normal loss. This occurs due to reasons such as evaporation, wastage, or spoilage. If the actual material loss exceeds this expected normal loss, the surplus is identified as abnormal loss.
The calculation for abnormal loss is as follows:
Abnormal Loss = Actual Loss – Normal Loss
This excess loss is then allocated directly to the Costing Profit and Loss Account, ensuring an accurate production cost calculation. Consequently, abnormal loss serves as an indicator of process inefficiencies.