成本会计复习提纲(精简版).doc

CHAPTER1
INTRODUCTION TO COST ACCOUNTING

cost management：identifies, collects, measures, classifies, and reports information that is useful to managers in costing (determining what something costs), planning, controlling, and decision making
什么是成本会计：成本会计是收集、整理成本信息，计算产品、劳动等成本对象的成本，并利用成本信息来编制企业的财务报表、进行成本控制和为企业的内部经营与决策踢空依据的管理活动。

问答：Explain the relationship between the Financial Accounting System and the Cost Management System？

答案：A financial accounting system is mainly concerned with producing information for the company’s external users. Financial accounting information is used for investment decisions, stewardship evaluation, activity monitoring, and regulatory measures. The rules that govern a financial accounting system are defined by the Securities Exchange commission (SEC) and the Financial Accounting Standards Board (FASB). Outputs of a financial accounting system include the standard financial statements which include the income statement, balance sheet, and the statement of cash flows.

The cost management system is concerned with producing information for the company’s internal users and is designed to meet management objectives. A cost management system has three broad objectives - to provide information on: costing of products and services, planning and control activities, and decision making activities.

CHAPTER 2
BASIC COST MANAGEMENT CONCEPTS
基本概念：
• Cost Objects are anything for which costs are measured and assigned. They may include: products, customers, departments, projects, activities, and so on.
Example： a bicycle is a cost object when you are determining the cost to produce a bicycle.
• Activity: A basic unit of work performed within an organization.
Example： setting up equipment, moving materials, maintaining equipment and designing products.
• Indirect costs: Costs that cannot be easily and accurately traced to a cost object.
Example： the salary of a plant manager, where departments within the plant are defined as the cost objects.
• Direct costs: Costs that can be easily and accurately traced to a cost object.
Example： the salary of a supervisor of a department, where the department is defined as the cost object, or bricks delivered to a house that is being constructed by a contractor, where the house is the cost object.
• Traceability: The ability to assign a cost to a cost object in an economically feasible way by means of a causal relationship.
• Driver:The factors that cause changes in resource usage, activity usage, cost, and revenues.
• Allocation: The least accurate cost assignment method. Often, no causal relationship exists between the cost and the basis used to assign the cost to the cost object.Assignment of indirect costs to cost objects is called allocation.
Prime Cost is the sum of direct materials cost and direct labor cost.
Conversion Cost is the sum of direct labor cost and overhead cost.

EXTERNAL FINANCIAL STATEMENTS

Income statement rely on:
Cost of goods manufactured
Cost of goods sold

Production costs are assigned to products or services and do not become expenses until the point of sale. Marketing and administrative costs are period costs and are deducted as an expense on the income statement in the period incurred. Nonproduction costs do not appear on the balance sheet.

Example:The cost of goods sold for the Tricky Corporation for the month of June 2011 was $450,000. Work-in-process inventory at the end of June was 95 percent of the work-in-process inventory at the beginning of the month. Overhead is 80 percent of the direct labor cost. During the month, $110,000 of direct materials were purchased. Revenues for Tricky were $600,000, and the selling and administrative costs were $70,000. Other information about Tricky's inventories and production for June was as follows:

Ending inventories-June 30

     Direct materials
$ 19,000
     Work in process
?
     Finished goods
105,000

Beginning inventories-June 1

     Direct materials
$ 22,200
     Work in process
40,000
     Finished goods
208,500
Required:

a.
Prepare a cost of goods manufactured and cost of goods sold statements.
b.
Prepare an income statement.
c.
What are the prime costs, conversion costs, and period costs?

ANS:
Tricky Corporation
Statement of Cost of Goods Manufactured
For Month of June 2011
Direct materials:

Beginning inventory*
$  22,200
Add: Purchases*
110,000
Materials available
$132200
Less: Ending inventory*
19,000
Direct materials used in production
$113,200
Direct labor
128,500
Manufacturing overhead ($128,500 × 0.80)
102,800
Total manufacturing costs added
$344,500
Add: Beginning work in process *
40,000
Less: Ending work in process ($40,000 × 0.95)
38,000
Cost of goods manufactured (from COGS statement)
$346,500
DM used = $22,200 + $110,000 – $19,000 = $113,200
CGM = $450,000 + $105,000 – $208,500 = $346,500
Total manufacturing costs added = DM + DL + MOH

$344,500 = 113,200 + DL + MOH

$231,300 = DL + MOH

$231,300 = DL + {MOH = 0.80 × DL}

$231,300 = DL + .8DL

$231,300 = 1.8DL

$128,500 = DL

 MOH = 0.80 × DL

 MOH = 0.80 × 128,500 = 102,800
Tricky Company
Statement of Cost of Goods Sold
For Month of June 2011
Cost of goods manufactured
$346,500
Add:Beginning finished goods*
208,500
Cost of goods available for sale
$555,000
Less: Ending finished goods*
105,000
Cost of Goods Sold*
$450,000
*These items are provided.

Tricky Company
Income Statement
For Month of June 2011
Sales*

$600,000
Less: Cost of goods sold*:

Add: Cost of goods manufactured
$346,500

Beginning inventory finished goods*
208,500

Cost of goods available for sale
$555,000

Less: Ending inventory finished goods*
105,000
450,000
Gross margin

$150,000
Less operating expenses:
Selling expenses*
Administrative expenses*

70,000
Operating Income

$ 80,000

Conversion costs= direct labor and overhead = = $128,500 + $102,800 = $231,300
Prime costs = DM + DL = $113,200 + $128,500 = $241,700
Period costs = $70,000

CHAPTER3
COST BEHAVIOUR

定义：成本总额与特定业务量在数量方面的依存关系（whether a cost changes when the level of output changes）。
1. 基本概念

fixed cost：in total are constant within the relevant range as the level of the activity driver varies.
variable cost：in total, vary in direct proportion to changes in an activity driver.
mixed cost：the cost that have both a fixed and a variable component.

在相关范围内，随着业务量的增加，总固定成本保持不变，单位固定成本逐渐减少，总变动成本逐渐增加，单位变动成本保持不变。相关范围（relevant range）不会改变固定成本和变动成本性态的有关区间和业务量的特定变动范围。

2. 分解混合成本
1) 三种定量方法：高低点法，散点图法，最小二乘法
Y = F + VX （需要估算F与V的值）

高低点法（high-low method）
基本原理：两点确定一条直线
注意：一定要选取业务量的最高与最低的两点为目标（highest activity level and lowest activity level）——也就是X轴上的最大最小值。千万不要错选了成本的最高最低点。
*例题：3-4书上P62页
优点：1.客观；2.计算简单
缺点：1.可能选到异常点（outlier）；2.即使不是异常点，选到的两个点可能不具有代表性

CHAPTER4
ACTIVITY-BASED COSTING
定义：作业成本法是以作业为核算对象，通过作业成本动因来确认和计量作业量，进而以作业成本动因分配率来对多种产品合理分配简介费用的成本计算方法
activity–based cost (ABC) system
a cost accounting system that uses both unit– and non–unit based cost drivers to assign costs to cost objects by first tracing costs to activities and then tracing costs from activities to products.

单位层次下的成本计量方法——分配制造费用
预定的制造费用分配率（predetermined overhead rate）= budgeted annual overhead / budgeted annual driver level
已分配的制造费用（applied overhead）= overhead rate ×activity driver usage

两种：1.plantwide rates ；2.departmental rates

Plantwide rates:
只用一个动因来分配成本，一般就是direct labor hour，然后得到唯一的plantwide rate
来计算applied overhead.
书上例题：4-1 P92页

制造费用差异（overhead variance）= actual overhead – applied overhead
如果actual overhead大于applied overhead,则该overhead variance称为underapplied overhead
如果actual overhead小于applied overhead,则该overhead variance称为overapplied overhead
对制造费用差异的处理：
如果该制造费用差异是不重要的（immaterial）：则全部分配到COGS中去；
如果该制造费用差异是重要的（material）：则按比例分配到WIP inventory，finished goods inventory 和COGS中去。
书上例题：4-2 P93页

Departmental rates：
第一步：确定每个部门所应使用的动因，然后计算出所有的部门制造费用率（departmental rate），有n个部门就会有n个部门制造费用率；
第二步：用这n个部门制造费用率将所有的制造费用分配到每种产品中去。
书上例题：4-3 P96页

Plantwide rate和departmental rate 的缺陷：
当overhead cost 占总成本的比率较低时，这两种简单易算的方法很适用；但是，当overhead cost占总成本的份额较高时，如果：1.非单位层次的制造费用比重太高，以及2.产品的多样性程度太高，那么使用这两种方法会造成成本扭曲（cost distortion），既制造费用分配不准确。

注意: 如果非单位层次动因的比例一致，就不会有成本扭曲。
某种产品使用每个作业的比率称之为消耗率（consumption ratio）

作业成本法分配制造费用
成本归集到作业，作业归集到产品。
步骤一：利用每个activity所对应的activity driver计算作业率（activity rate）
activity rate =activity overhead cost/activity usage
有n个activity，就会有n个activity driver，也就会有n个activity rate
步骤二：把某个产品实际消耗的每种作业的作业量乘以对应的activity rate，再加总便可得到该产品所使用的overhead cost——product cost = Σactivity rate × activity usage
书上例题： 4-5 P101页

例题
The Juneau plant produces two calculators and has two production departments: assembly and packaging. Information for the products is given below:

Deluxe
Regular
Total
Units produced
20,000
200,000

Prime costs
$160,000
$1,500,000
$1,660,000
Direct labor hours
20,000
160,000
180,000
Number of setups
60
40
100
Machine hours
10,000
80,000
90,000
Inspection hours
2,000
16,000
18,000
Number of moves
180
120
300

The following table presents activity information about the departments and products:

Assembly
Packaging
Total
Direct labor hours:

Deluxe
10,000
10,000
20,000
Regular
150,000
10,000
160,000
Total
160,000
20,000
180,000
Machine hours:

Deluxe
2,000
8,000
10,000
Regular
8,000
72,000
80,000
Total
10,000
80,000
90,000
Overhead Costs:

Setting equipment
$120,000
$ 120,000
$240,000
Moving material
60,000
60,000
120,000
Machining
20,000
180,000
200,000
Inspection
16,000
144,000
160000
Total
$216,000
$504,000
$720,000

Required:

a.
Compute the predetermined overhead rate for each department if Assembly uses labor hours and Packaging uses machine hours.

b.
Calculate the per unit cost for each product if departmental overhead rates are used. (Round to 2 decimal places.)

c.
Compute the predetermined plant-wide overhead rate based on direct labor hours.

d.
Calculate the per unit cost of each product if a plantwide overhead rate is used. (Round to 2 decimal places.)

e.
Calculate the overhead rates for each overhead activity.

f.
Calculate the per unit cost of each product if a activity rates are used to assign overhead.
(Round to 2 decimal places.)

ANS:

a.
Assembly
$ 216,000

Labor hours
160,000

Overhead rate
$1.35

Packaging
$504,000

Machine hours
80,000

Overhead rate
$6.30

b.

Deluxe
Regular
Units
20,000
200,000
Prime costs
$160,000
$1,500,000
Overhead applied to production

Assembly:

1.35 x 10,000
13,500

1.35 x 150,000

202,500
Packaging

6.30 x 8,000
50,400

6.30 x 72,000

453,600
Total
$223,900
$2,156,100
Overhead per Unit
$11.20
$10.78

c. $720,000/180,000 = $4 per labor hour

d.

Deluxe
Regular
Units
20,000
200,000
Prime costs
$160,000
$1,500,000
Overhead costs

4 x 20,000
80,000

4 x 160,000
---
640,000
Total costs
$240,000
$2,140,000
Unit cost
$12
$10.70

e.

Activity
Cost
Driver
Activity Rate
Setting up equip
$240,000
100
$2,400 per setup
Moving material
$120,000
300
$400 per move
Machining
$200,000
90,000
$2.22 machine hour
Inspecting
$160,000
18,000
$8.89 per inspection hours

f.

Deluxe
Regular
Units
20,000
200,000
Prime costs
$160,000
$1,500,000
Overhead costs:
Setting up

$2,400 x 60
144,000

$2400 x 40

96,000
Moving materials

$400 x 180
72,000

$400 x 120

48,000
Machining

$2.22 x 10,000
22,200

$2.22 x 80,000

177,600
Inspecting

$8.89 x 2000
17,780

$8.89 x 16,000

142,240
Total costs
$415,980
$1,963,840
Unit cost
$20.80
$9.82

主要作业（primary activity）：最终成本对象（final cost object）所消耗的作业
次级作业（secondary activity）：中间成本对象（intermediate cost object）所消耗的作业
把次级作业分配到主要作业中去——书上例题4-6 P108页

CHAPTER 5
PRODUCT AND SERVICE COSTING:JOB-ORDER SYSTEM
基本概念：
The differences between job-order costing and process costing:
1. A job-order costing system accumulates production costs by job; a process-costing system accumulates production costs by process.
2. The job-order costing system uses a single work-in-process account, while the process-costing system has a WIP account for every process.
3. Job-order costing is suitable for operations that produce custom-made products that receive different doses of manufacturing costs. Process costing, on the other hand, is suitable for operations that produce homogeneous products that receive equal doses of manufacturing costs in each process.

分批法的基本特点：
1．以产品的批别（或定单）作为成本计算对象。
2．制造费用是按照预定分配率（predetermined overhead rate）来分配的。
3．成本计算期不固定。与生产周期一致，与会计报告期不一致。但要注意，分批法下仍然要按月结帐。
4．完工产品与在产品费用分配一般不存在，因为：
全部完工......全为完工产品成本
在产品月末状态 全未完工......全为在产品成本
部分完工......一般不分配

关于制造费用（Manufacturing overhead）的分配问题

一. 对overhead control这个账户的理解：
1. 可分解为3个账户：实际数、计划数、差异数
2.
Overhead Control
actual overhead
applied overhead

overhead variance
(over applied)

Overhead Control
actual overhead
applied overhead

overhead variance
(under applied)

值得注意的是，只有applied overhead才能够分配到 WIP 中，因为 job-order costing 采用normal costing的方法。
二．对overhead variance的处理：
1. 当差异额没有达到重要性水平时，直接将其转至Cost of Goods Sold账户
2. 当差异额达到重要性水平时，按一定比率分配至WIP ,FG 和Cost of Goods Sold
三个账户中。

CHAPTER 6
PROCESS COSTING

定义：分步法是以产品的品种及其所经过的生产步骤作为成本计算对象，归集生产费用，计算各种产品成本及其各步骤成本的一种方法。它主要适用于大量大批复杂生产的企业，如纺织、冶金、造纸等大量大批多步骤生产类型的企业。

分步法的基本特点：
1. 成本计算对象为各种产品的生产步骤和产品品种。
2. 成本计算是定期于月末进行与会计报告期一致，和生产周期不一致。
3. 生产费用需要在完工产品与在产品之间分配。
4. 各步骤之间需进行成本结转。
5. 成本计算采用累加的方法。用T账户来表示的成本流转示意图（假设无在产品）：

基本概念图： Units to account for
Unit information
Units accounted for
1. 生产报告（Production report）
Costs to account for
Cost information
Costs accounted for

WIP
__________________________________
Beginning WIP
2. Costs to account for
Current costs
Costs of units transferred out
__________________________________ Costs accounted for
Ending WIP

3. 约当产量（Equivalent units）
(1)加权平均法（Weighted average metho