RE-COMPUTING THE COST OF GOODS MANUFACTURED OF A BROWNIE ORDER USING JOB-ORDER COSTING: A SECONDARY-DATA CASE STUDY OF TOMANG BAKERY, MEDAN

Abstract

Accurate unit cost information is essential for micro, small, and medium enterprises (MSMEs) that produce to order, because selling prices are usually set as a markup on cost. Siregar et al. (2024) reported that one box of brownies at Tomang Bakery, Medan, costs IDR 58,035 to produce and should sell for IDR 81,249 with a 40% markup, slightly above the bakery's price of IDR 80,000. This study re-analyses their published data using the job-order costing framework of Brewer, Garrison, and Noreen (2019). Cost data were extracted from the original tables, checked arithmetically, reclassified into direct materials, direct labor, and manufacturing overhead, and compiled in a job cost sheet and a schedule of cost of goods manufactured. The check found that the equipment depreciation total in the source already includes the machine depreciation reported separately, and that the depreciation of the digital cake weigher is miscalculated. The corrected cost is IDR 55,125 per box, 5.0% lower than reported, and the 40% markup price is IDR 77,175. The bakery's price of IDR 80,000 is therefore IDR 2,825 above the markup price instead of below it, which reverses the original conclusion. A sensitivity analysis shows that treating depreciation as a fixed cost, as variable costing requires, lowers the markup price to IDR 72,380, although this result depends on the cost-behavior assumption. The findings show that arithmetic verification and a consistent costing framework can change pricing conclusions for MSMEs.