本研究提出一個製造業成本計算模型來說明製造業成本計算系統的運作流程。製造業成本計算系統介於 ERP 系統與會計總帳之間,成本計算是處理原物料、在製品、製成品等三種存貨帳戶之間數量進出與金額之轉換。本研究特別探討在製品的數量與金額如何計算,以做為分攤直接人工費用與製造費用之基礎。 同時,本研究提出的模型把分步成本制混合成「變形分步成本制」,結合製程與 BOM 用料清單,把多個站別之分步成本整合成單一約當產量之分步成本,透過此約當產量即可從標準成本推導出實際成本。在每一會計期間結束時,本期實際成本可與標準成本加以比較,得以評估本期績效優劣,以改進企業之成本競爭力。
This study proposes a model to describe the operational process of manufacturing costing system. The costing system bridges the gap between the ERP system and the general accounting system. Manufacturing costing deals with the quantity and cost transformation among the inventory accounts of the raw material, work in process (WIP) and finished goods. This study especially discusses the transformation of WIP’s quantities and amounts, which then serves as the basis of defining the apportionment of direct labor cost and factory overhead. The contribution of this study is an operating model to integrate the step-by-step process costing into mixed process costing. This model combines the bill of material (BOM) with manufacturing processes to unify several stations’ process costs into equivalent units’ process cost. With these equivalent units of production, the actual costs are derived from the standard cost throughout an enterprise daily operation. A manufacturing enterprise can use this model to evaluate its annual performance by comparing the actual costs with the standard costs at the end of the fiscal year.