Notes on Product Costing, Absorption Costing, and Cost Allocation Methods

Absorption costing and the role of product vs. period costs

  • Absorption costing (full costing) assigns all manufacturing costs (direct materials, direct labor, manufacturing overhead) to products.

  • Product costs: DM, DL, MOH. These costs are inventoried on the balance sheet until the product is sold.

  • Period costs: Selling and administrative (non-manufacturing) costs expensed in the period incurred.

  • Uses of cost information:

    • Report inventories and cost of goods sold on the financial statements.

    • Decision making for long-term and short-term (routine and non-routine) decisions.

    • Planning and operational control.

  • Under absorption costing, product costs remain in inventories on the balance sheet until sold; period costs are expensed as incurred.

Roles and purposes of cost information (overview)

  • Value inventories and COGS for financial reporting.

  • Support decision making across time horizons (long-term decisions, and short-term, routine or non-routine decisions).

  • Aid planning and operational control through cost visibility.

Components and flows of product costs

  • Manufacturing costs consist of:

    • Direct materials (DM)

    • Direct labor (DL)

    • Manufacturing overhead (MOH) → indirect materials, indirect labor, depreciation of manufacturing equipment, utilities, maintenance, factory supervision, etc.

  • Prime costs vs. conversion costs:

    • Prime costs = Direct materials + Direct labor

    • Conversion costs = Direct labor + Manufacturing overhead

  • Flow of costs through accounts:

    • Raw materials → Work-in-Process (WIP) → Finished goods → Cost of goods sold (COGS)

    • Some costs are recorded as inventory (asset) until sold; COGS is expensed when goods are sold.

  • Inventory relationships:

    • Inventories on the Balance Sheet are increased by product costs and decreased when goods are sold.

    • COGS appears on the Income Statement when products are sold.

Product costs under absorption costing (summary diagram terms)

  • Manufacturing costs (DM + DL + MOH) contribute to Inventories on the Statement of Financial Position.

  • COGS (COGS) is the expense on the Income Statement when products are sold.

  • Non-manufacturing costs (Selling & Distribution, Administrative) are period costs.

Direct materials, direct labor, and manufacturing overhead (MOH)

  • Direct materials (traceable directly and conveniently to a product).

  • Direct labor (labor cost of workers directly involved in production).

  • Manufacturing overhead (all other manufacturing costs not directly traceable to a product):

    • Indirect materials, indirect labor, depreciation of factory equipment, factory utilities, maintenance, quality control, supervision, and other overhead items.

  • Material cost flow considerations:

    • Material costs can be tracked using FIFO, weighted-average (Average), or specific identification methods for costing purposes.

  • The allocation of MOH is needed to assign indirect production costs to individual products/jobs.

Flow of manufacturing costs (detailed)

  • Manufacturing costs include: Direct materials, Direct labor, Manufacturing overhead.

  • In the flow: Direct materials + Direct labor + MOH flow into WIP; completed goods move to Finished Goods; upon sale, COGS.

  • Non-manufacturing costs are expensed as incurred.

  • From the example visuals: Product costs are accumulated in inventories (WIP, FG) until sold; when sold, they become COGS in the income statement.

Details of manufacturing costs and cost flows (per slides 9–12)

  • Manufacturing costs flow: Materials → Labor → MOH → WIP → Finished Goods → COGS.

  • Direct materials and direct labor are the traceable costs that can be assigned to specific products.

  • MOH consists of costs that cannot be traced directly to a product but are necessary for production.

  • Prices for materials may be tracked by different cost flow assumptions (FIFO, Average, Specific Identification).

Non-manufacturing costs and manufacturing cost items (examples)

  • Direct materials: Fruits, sugar, packaging (illustrative product examples used in slides).

  • Direct labor: Workers directly involved in production.

  • Manufacturing overhead: Indirect materials, indirect labor (supervisors, maintenance), depreciation, utilities, insurance, taxes, etc.

  • Non-manufacturing costs: Selling, distribution, and administrative costs.

MOH allocation and methods of cost valuation (overview)

  • Objective: Allocate indirect production costs to products/jobs.

  • Common methods:

    • Actual costing

    • Normal costing

    • Standard costing

  • Allocation bases (cost drivers):

    • Plant-wide or departmental rates

    • Direct materials, direct labor hours, machine hours, or other cost drivers

    • Allocation basis should reflect the consumption of MOH by products/jobs

  • Key questions when allocating MOH:

    • Use actual or pre-determined rates?

    • Use a single plant-wide rate or multiple departmental rates?

    • What allocation basis should be used?

Actual costing vs pre-determined vs normal costing (formulas)

  • Actual costing: Overhead rate and application

    • ext{MOH Rate}_{ ext{Actual}} = rac{ ext{Actual manufacturing overhead costs}}{ ext{Actual quantity of allocation base}}

    • ext{MOH absorbed} = ext{MOH Rate}_{ ext{Actual}} imes ext{Actual quantity of allocation base used}

  • Pre-determined (applied) MOH rate (used in normal costing):

    • ext{MOH Rate}_{ ext{Applied}} = rac{ ext{Estimated total manufacturing overhead costs}}{ ext{Estimated total quantity of allocation base for the year}}

    • Then MOH absorbed to products = ext{MOH Rate}_{ ext{Applied}} imes ext{Actual quantity of allocation base used for the product/job}

  • Standard costing uses standard MOH costs, with variance analysis (not detailed in the slides but conceptually similar to standard costing in other chapters).

Actual costing (example calculations)

  • Example XYZ Co., Ltd. (furniture) MOH costs (for the month):

    • Indirect materials: 30,000

    • Indirect labor: 120,000

    • Supervisors’ salaries: 350,000

    • Insurance: 15,000

    • Property taxes: 5,000

    • Depreciation: 70,000

    • Utilities: 30,000

    • Miscellaneous: 10,000

    • Total MOH: 630,000

  • Activity data for products A and B:

    • Direct labor hours A: 12,000; B: 18,000 (Total DL hours: 30,000)

    • Machine hours A: 10,000; B: 12,500 (Total machine hours: 22,500)

  • Allocation options and results:

    • Single rate based on DL hours:

    • ext{MOH Rate} = rac{630{,}000}{30{,}000} = 21 ext{ per DL hour}

    • A MOH absorbed = 21 imes 12{,}000 = 252{,}000

    • B MOH absorbed = 21 imes 18{,}000 = 378{,}000

    • Single rate based on machine hours:

    • ext{MOH Rate} = rac{630{,}000}{22{,}500} = 28 ext{ per machine hour}

    • A MOH absorbed = 28 imes 10{,}000 = 280{,}000

    • B MOH absorbed = 28 imes 12{,}500 = 350{,}000

    • Departmental rates in the two departments (machining and assembly):

    • Machining dept MOH: 450,000; Allocation base: machine hours 22,500 → ext{MOH Rate}_{ ext{Machining}} = rac{450{,}000}{22{,}500} = 20 ext{ per machine hour}

    • Assembly dept MOH: 180,000; Allocation base: direct labour hours 24,000 → ext{MOH Rate}_{ ext{Assembly}} = rac{180{,}000}{24{,}000} = 7.5 ext{ per DL hour}

  • Departmental rate absorption for products A & B (example data):

    • Product A: Machining 10,000 hours × 20 = 200,000; Assembly 10,000 DL hours × 7.5 = 75,000; Total MOH absorbed = 275,000

    • Product B: Machining 12,500 hours × 20 = 250,000; Assembly 14,000 DL hours × 7.5 = 105,000; Total MOH absorbed = 355,000

  • Comparison (MOH absorbed) under different approaches (illustrative values):

    • Single rate based on DL hours: A = 252,000; B = 378,000

    • Single rate based on machine hours: A = 280,000; B = 350,000

    • Departmental rates: A = 275,000; B = 355,000

Limitations of actual costing (flow and timing issues)

  • It takes time to gather all MOH cost information.

  • Unit product cost under actual costing is sensitive to fluctuations in actual production volume each period.

MOH allocation under normal costing (pre-determined rate at year start)

  • Steps for normal costing system: 1) At the beginning of the year, estimate MOH costs and the allocation base quantity to determine the pre-determined rate.

    • No accounting record is required yet.
      2) When completing a job or at month-end, apply MOH using the pre-determined rate.
      3) Record actual MOH costs as incurred in their respective accounts.
      4) At month-end, compare actual MOH with MOH applied and record over- or under-applied MOH.
      5) At year-end, close the over/under-applied MOH account by prorating to WIP, FG, and COGS or adjust COGS only.

  • Example ABC Ltd (Normal Costing):

    • Budgeted data: Estimated MOH costs = 8,000,000; Units of production = 1,200,000; Direct materials = 4,800,000; Machine hours = 32,000; Direct labor hours = 40,000; Direct labor costs = 2,000,000.

    • Rate basis: single plant-wide rate using direct labor cost as the allocation base.

  • Example – Normal costing with single rate (DL cost basis):

    • Actual DL costs for the month: X = 72,000; Y = 90,000; Total DL costs = 162,000.

    • Indirect materials = 10,000; Indirect labor = 150,000; Others = 490,000; Total MOH incurred = 650,000.

    • Pre-determined MOH rate = rac{8{,}000{,}000}{2{,}000{,}000} = 400 ext{%} (i.e., 400% of DL cost).

    • MOH applied: X = 400% × 72,000 = 288,000; Y = 400% × 90,000 = 360,000; Total MOH applied = 648,000.

    • Actual MOH costs recorded: 650,000.

    • Month-end variance: Underapplied MOH = 2,000 (650,000 − 648,000).

    • Year-end close: adjust COGS or prorate to WIP/FG/COGS as appropriate.

  • Quick checks:

    • Tiger, Inc. example: Actual MOH = 1,210,000; Predetermined rate = $4.00 per machine hour; Hours = 290,000.

    • Applied MOH = 4.00 × 290,000 = 1,160,000.

    • Over/under: Actual > Applied → Underapplied by 50,000.

    • Correct answer: b) $50,000 underapplied.

Cost accumulation systems: Job costing vs. Process costing

  • Job costing

    • Traces costs to specific jobs.

    • Suitable for small quantities, batches of uniquely identifiable or tailor-made products, or services.

    • Uses job cost sheets; tracks costs by job with a unique job number.

    • Costs tracked by job: Direct materials, direct labor, and allocated MOH at job completion or periodically.

    • Unit product cost for a job = Total product costs for the job / Units produced for the job.

  • Process costing

    • Traces costs by department or process for large quantities of homogeneous products.

    • Suitable when processes produce identical units.

    • Costs flow through departments; unit product cost = Total product costs for the period / Units produced for the period.

  • Which system to use depends on the operation process and the nature of the product.

Process costing: unit cost and equivalent units (key concepts and formulas)

  • Unit product cost in a processing environment:

    • ext{Unit product cost} = rac{ ext{Total product costs for the period}}{ ext{Units of production for the period}}

  • Equivalent units of production (EUP):

    • If some units are not fully completed, convert them to an equivalent number of fully completed units.

    • Example concept: If 6,000 units are finished and there is 4,000 units in ending WIP at 50% complete, then total equivalent units = 6,000 + (0.50 × 4,000) = 8,000.

    • Cost per equivalent unit = Total costs in department / Equivalent units of production.

  • Process costing in multiple departments:

    • Compute cost per equivalent unit in each department separately (DM, DL, MOH in that department).

    • Allocate costs to units transferred and to ending WIP based on equivalent units in each department.

Process costing examples (highlights from slides)

  • Example 1 (No beginning WIP):

    • Departments: Preparation, Cooking, Packaging.

    • Units finished and transferred: 10,000 in each department.

    • Costs incurred per department: $10,000 (Preparation), $30,000 (Cooking), $60,000 (Packaging).

    • Equivalent units per department: 10,000 in each (no ending WIP).

    • Cost per unit per department: $1.00, $3.00, $6.00 respectively.

    • Transfer costs equal the costs incurred per department for the units transferred.

  • Example 2 (Ending WIP):

    • Ending WIP in Packaging department = 4,000 at 50% completion; Finished & transferred = 6,000.

    • Cost incurred in the department = $10,000 ( Preparation ), etc. (illustrative).

    • Equivalent units = 6,000 + (50% × 4,000) = 8,000; Cost per unit determined accordingly (e.g., $1.25 per unit in that department in the example).

  • Example 3 (Equivalent units by inputs):

    • Different inputs (DM, DL, MOH) can have different completion percentages; compute separate equivalent units for each input and derive per-unit costs accordingly (e.g., DM = 80 total cost with 2 units at 100%, DL = 30 with 2 units at 75%, MOH = 45 with 2 units at 75%; derive 2 units, 100% = costs / 2; 2 units, 75% = (cost) / 1.5, etc.).

Job costing vs. process costing: quick recap

  • Job costing: costs traced to specific jobs; best for customized or small-batch products; unit cost = total job costs / units produced for the job.

  • Process costing: costs traced by department/process; best for homogeneous, high-volume production; unit cost = total costs / units produced; uses equivalent units for partial completion.

Quick practice questions and checks (conceptual reminders)

  • Determine whether to use job costing or process costing based on product type and production process.

  • For MOH allocation, decide between actual vs pre-determined rates, and whether to use plant-wide or departmental bases.

  • Understand under- and over-applied MOH: difference between actual MOH and MOH applied; decide whether to close to COGS or prorate to WIP/FG/COGS at period-end.

  • Remember that normal costing uses a pre-determined MOH rate (based on estimates) for the year; actual MOH costs are recorded as incurred and compared to applied MOH.

Summary (key takeaways)

  • Absorption costing requires that product costs (DM, DL, MOH) be included in inventory until sale; period costs are expensed as incurred.

  • MOH allocation is essential because MOH cannot be traced directly to individual units; it is allocated using rates based on a chosen allocation base.

  • Allocation methods include Actual costing, Normal costing (pre-determined rate), and Standard costing; departmental vs. plant-wide rates affect accuracy.

  • The choice of allocation base (DL hours, machine hours, DL cost, etc.) and the rate calculation method impact the reported product costs and profitability.

  • Job costing vs. process costing: determine the best system based on customization vs. mass production; each has distinct formulas for unit costs and cost accumulation.

  • Equivalent units are crucial in process costing to account for partially completed units in ending WIP and to compute accurate unit costs.

Notation and equations (recap)

  • MOH Rate (Actual):

    • ext{MOH Rate}_{ ext{Actual}} = rac{ ext{Actual manufacturing overhead costs}}{ ext{Actual quantity of allocation base}}

  • MOH Absorbed (Actual):

    • ext{MOH absorbed} = ext{MOH Rate}_{ ext{Actual}} imes ext{Actual quantity of allocation base used}

  • MOH Rate (Applied / Predetermined):

    • ext{MOH Rate}_{ ext{Applied}} = rac{ ext{Estimated MOH costs}}{ ext{Estimated total allocation base}}

  • MOH absorbed (Applied) under normal costing:

    • ext{MOH absorbed} = ext{MOH Rate}_{ ext{Applied}} imes ext{Actual allocation base used}

  • Process costing unit cost (departmental):

    • ext{Unit cost in department} = rac{ ext{Total department costs}}{ ext{Equivalent units in department}}

  • Process costing unit product cost (period):

    • ext{Unit product cost} = rac{ ext{Total product costs for the period}}{ ext{Units of production for the period}}

  • Equivalent units (example):

    • If Finished = 6{,}000 units; Ending WIP = 4{,}000 units at 50% completion →

    • ext{Equivalent units} = 6{,}000 + (0.50 imes 4{,}000) = 8{,}000

  • Pre-determined rate example (400%):

    • ext{Pre-determined MOH rate} = rac{8{,}000{,}000}{2{,}000{,}000} = 400 ext{%}

  • Quick check answer example (Tiger, Inc.):

    • Applied MOH = 4.00 imes 290{,}000 = 1{,}160{,}000

    • Actual MOH = 1{,}210{,}000 $$

    • Underapplied MOH = 1{,}210{,}000 - 1{,}160{,}000 = 50{,}000

(Note: All figures in the notes reflect the numbers and examples from the provided transcript.)