Duh的部落格

2019/4/29 Activity-Based Costing _ Calculation Steps and Example作業成本法 |計算步驟和範例

Activity-Based Costing作業成本法

Activity-based costing is a method of assigning indirect costs to products and services |by identifying cost of each activity involved in the production process |and assigning these costs to each product based on its consumption of each activity.

首先,作業成本法 是一種分配 間接成本 到 產品與服務 的方法 |

藉由 識別 生產過程中 的每項活動成本 | 以及 基於 這項 活動的 消耗量 將這些成本分配到每項產品之中

=每項活動的成本組成=產品本身的成本+生產過程中活動的消耗量

Activity-based costing is a more refined approach to costing products and services than the traditional cost allocation methods.

另外,作業成本法也是一種 以計算生產和服務 來說 比過去傳統成本法 更優的 分配 方法

它包含了以下７個步驟:It involves the following steps:

• 識別生產過程中參與的活動Identification of activities involved in the production process;
• 根據成本層級的不同　來　分類每項活動　(即指單位層級，批量層級，產品層級和設施層級)

Classification of each activity according to the cost hierarchy (i.e. into unit-level, batch-level,　product-level, and facility-level);

• 判別與累計合併每項活動的總成本Identification and accumulation of total costs of each activity;
• 為每項活動找出最適合的成本導向Identification of the most appropriate cost driver (allocation base) for each activity;
• 計算對應於每項活動的總單位成本動因Calculation of total units of the cost driver relevant to each activity
• 計算活動率 也就是指 計算 每相關成本動因單位的每項活動的總成本Calculation of the activity rate i.e. the total cost of each activity per unit of its relevant cost driver;
• 根據產品的活動量(使用情況) 將 每項(活動的)成本 對應 到 產品Application of the cost of each activity to products based on its activity usage by the product.

Cost Hierarchy成本層級

作業成本法的第一步 包含了 根據成本層級 識別活動 和 進行分類

The first step in activity-based costing involves identifying activities and classifying them according to the cost hierarchy.

Cost hierarchy is a framework that classifies activities based the ease at which they are traceable to a product.

成本層級 的 架構 是 根據活動 追朔產品. 的容易度 再將之進行分類

The levels are (a) unit level, (b) batch level, (c) product level, and (d) facility level.

共分為四個層級,為是單位層級，批量層級，產品層級還是設施層級

Unit level activities are activities that are performed on each unit of product.

單位層級活動 是指 每項產品單位 執行的活動

Batch level activities are activities that are performed whenever a batch of the product is produced.

批量層級活動 是指 每批產品生產時 執行的活動

Product level activities are activities that are conducted separately for each product.

產品層級活動 是指 每項產品 各自進行的活動

Facility level activities are activities that are conducted at the plant level.

設施層級活動 是指 在生產性工廠 進行的活動 plant 特指生产性的工厂

其中，單位層級活動最容易追朔到產品, 而設施層級最難追朔到產品

The unit-level activities are most easily traceable to products  while facility- level activities are least traceable.

http://www.baike.com/wiki/%E4%BD%9C%E4%B8%9A%E6%88%90%E6%9C%AC%E6%B3%95

Example: Application of Activity-Based Costing範例: 作業成本法的應用

Alex Erwin10年前開創了Interwood. 一個屬於小眾市場的家具品牌

Alex Erwin started Interwood, a niche furniture brand, 10 years ago.

 (A niche brand is one that is very meaningful to some people, but not applicable to most people.)

利基市場-小眾品牌對某些人來說非常具有意義性, 對多數人卻毫無關聯)

他獨資經營這個事業He ran the business as a sole proprietorship.

當他在旗下有50位純熟木工師傅與5位銷售業務的時候While he has 50 skilled carpenters and 5 salespeople on his payroll,

他都自己負責會計事務he has been taking care of the accounting by himself.

現在, 他打算在未來幾年提供40%的資本給大眾Now, he intends to offer 40% of the ownership to public in next couple years

也有意願改變，才會聘請你們來當管理會計（師），協助組織及改善（他們的）會計系統and is willing to make changes and has hired you as the management accountant to organize and improve  the accounting systems.

Interwood本年度總預算(生產開銷)為5百40萬4,639美元Interwood's total budgeted manufacturing overheads cost for the current year is  預估總工時為2萬小時內And budgeted total labor hours are 20,000.

Alex已採用傳統成本法整整10年Alex has been applying traditional costing method during the whole 10 years period

並依據總工時計算預定開銷率and based the pre-determined overhead rate on total labor hours.

Interwood的沙發提供了2人座.3人座及6人座的選擇Interwood's sofa range includes the 2-set, 3-set and 6-set options.

Platinum Interiors recently placed an order for 150 units of the 6-set type.

Platinum Interiors(英國的室內設計公司)最近下了150套6人座款式的訂單

https://www.platinum-interiors.com/ (白金室內設計, Mexborough,UK) 鉑/內飾

這份訂單期望能在一個月之內收到貨The order is expected to be delivered in one-month time.

由於是客製化訂單,Platinum 將會被加收成本25%的額外費用(按成本加計25%費用)

Since it is a customized order, Platinum will be billed at cost plus 25%.

你們不是 傳統生產成本系統的粉絲.You are not a fan of traditional product costing systems.

你們相信 作業成本法的 好處/優勢 超乎預期(超過成本)You believe that the benefits of activity-based costing system exceeds its costs,

所以 你們與主要工程師Aaron Mason開會討論. 密切合作(坐下來討論),Sit down with與某人坐下討論

so you sat down with Aaron Mason, the chief engineer,

以 識別/鑑定 公司內沙發部門的活動to identify the activities which the firm undertakes in its sofa division.

接著, 進入每項活動 計算成本總額 Next, you calculated the total cost that goes into each activity,

識別 與 每項活動最相關 的 成本動因 以及 計算活動比率identified the cost driver that is most relevant to each activity and calculated the activity rate.

結果合計如下:The results are summarized below:

一旦訂單準備好到包裝階段, Aaron給你 發生成本的總計金額, 　一份執行活動的詳細說明(也稱作:活動清單), 如下所示:

Once the order was ready for packaging, Aaron gave you a summary of total cost incurred,　and a statement of activities performed (also called the bill of activities) as shown below:

Part A: Traditional Costing System傳統成本法

Calculate the total cost of the order and the invoice value of the order based on traditional costing

system.以傳統成本法為基礎 計算 訂單的 總成本 和 發票面額

Solution解法

In the traditional costing system, cost equals materials cost plus labor cost plus manufacturing overhead

costs charged at the pre-determined overhead rate.

在傳統成本法,  成本 = 材料成本 + 人工成本 + 製造費用成本, 以此來收取預定開銷率

The pre-determined overhead rate based on direct labor hours = $5,404,639/20,000 = $270 per labor

hour預定開銷率的基礎建立在 直接人工時數 = $5,404,639/20,000 =每位勞工$270

人工時數花在一份訂單的實際數字是250The actual number of labor hours spent on the order is 250.

一旦我們有此數據, 我們便可以估算生產成本以及總成本, 舉例如下:

Once we have this data, we can estimate the manufacturing overheads and the total cost as follows:

直接材料25,000+採購的零件35,000+人工成本15,600=75,600 製造費用(生產成本) ($270 × 250) 67,500

使用傳統成本法的總成本為14萬3千1百

Interwood收取Platinum的成本外加25%, 總計金額為$17萬8千875 (= $143,100 × 1.25).

Part B: Calculating Total Cost under Activity-Based Costing以作業成本法 來 計算:

你知道作業成本法 是一種更正確的途徑. 現在, 自從你有了所有需要的數據, 用作業成本法 計算 訂單成本

You know activity-based costing is a more refined approach. Now, since you have all the data needed, calculate the order cost using activity-based costing.

Solution解法

在作業成本法, 直接材料成本, 購買零件成本 以及 人工成本 仍和傳統產品成本相同In activity-based costing, direct materials cost, cost of purchased components and labor cost remains the　same as in traditional product costing.

但是, “製造費用”被分配 的 價值 會更加準確地被估算出來

However, the value of manufacturing overheads assigned is more accurately estimated.

The following worksheet estimates the manufacturing overhead costs that should be assigned to the order of Platinum Interiors:

下面工作表 所 估計 應該被分配 到Platinum Interiors 訂單 的  製造費用為:

訂單的總計成本 於是 等於$197,150

根據更準確的訂單成本估算，發票應該提高到197,150美元（= $ 157,721×1.25）而不是傳統產品成本核算系統計算的178,875美元。

這個範例強調了 正確估算 產品成本  的重要性 及 作業成本法實現此目標的實際效果

example highlights the importance of correct estimation of the product cost and the usefulness of activity-based costing in achieving that goal.

這是因為做到精準的成本分配 對 判別有利潤的產品以及分配資源 來說 至關重要

It is because accurate allocation of cost is critical for identification of profitable products and allocating resources.

Written by Obaidullah Jan, ACA, CFA and last revised on Apr 3, 2019

Pre-determined Overhead Rate預期費用分攤率  Joint Products巨型產品  Job Order Costing工作單成本核算  Job Cost Sheet工作成本表

Process Costing流程成本核算  Process Costing – Weighted  Average Method重量平均法  Equivalent Units – Weighted約當產量

Average Method重量平均法  Process Costing – FIFO Method流程成本核算-先進先出法  Equivalent Units – FIFO Method約當產量-先進先出法

Activity-Based Costing作業成本法