成本会计 管理的着重点 第2章

适用范围：
这种方法适用于投入量与产出量管理比较稳定的新 企业及其重要成本的测算。
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Cost Function

WWC offers Cannon Services three alternative cost structures to use of a telephone line between New York and Paris.
Alternative1: $5 per minute of phone use. Alternative2: $10 000 per month Alternative3: $3 000 per month plus $2 per minute of phone use.
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Learning Objective 1
Explain the two assumptions frequently used in cost-behavior estimation
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Assumptions in Cost-Behavior Estimation
1.Changes in total costs can be explained by changes in the level of a single activity. 2. Cost behavior can adequately be approximated by a linear function within the relevant range.

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案例分析：
设单价为USP，单位变动成本为UVC 10USP-10UVC-30=10 即：（USP-UVC）=4 12USP-12UVC-30=12（USP-UVC）-30 =12*4-30=18 18-10=8 即：利润应增加8万元，实际 只增加了2万元。 所以，计划完成的很不理想。

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趋势分析
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is also called the work-measurement method. It estimates cost functions by analyzing the relationship between inputs and outputs in physical terms.
(工业工程法，也叫做技术测定法或工作测定法)
Variable costs per unit do not change as activity increases.
Per Minute Telephone Charge
Minutes Talked
Minutes Talked
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Fixed Costs
Fixed costs do not change in total for a given time period despite wide changes in the related level of total activity or volume. Fixed costs per unit decline as activity increases.
What is the cost function?
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Alternative 1:
y = cost
y = $5X y
Slope Coefficient （系数）
x = number of phone-minutes used
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x
Alternative2:
y = cost y
y = $10 000
0
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Relevant Range
Relevant Range
$16 000 – Fixed Costs $12 000 – $8 000 – $4 000 0 500 1 000 1 500 2 000 Volume in Units 2 500
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Relevant Range
–
–
–
Learning Objective 3
Total
1 400 000 1 480 000
Unit cost
10 9.87
从单位成本的概念而言，企业的成本无疑是下降了，表现为有 利差异0.13元，但这是否足以说明企业成本真正下降、企业成 本控制工作真正有效或者说8月份的绩效真正优于7月份呢？1
案例分析：
天航股份有限公司上年度计划产销某种产 品10万件，计划利润10万元。实际执行结 果是，产销该种产品12万件，实现利润12 万元。要求：试对该公司上年度的利润计 划完成情况作出评价。 注：固定成本总额为30万元，固定成本、 单位变动成本与售价均无变动
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Cost Estimation Approaches
Industrial engineering method
Conference method Account analysis method
Quantitative analysis methods
Objective!
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1/4Industrial Engineering Method

Whether a cost is variable or fixed with respect to a particular activity depends on the time span.
More costs are variable with longer time spans
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Relevant Range

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解 释：
它是由工程技术人员通过某种技
术方法测定正常生产流程中投 入——产出之间的规律性的联系， 以便逐项研究决定成本高低的每 个因素，并在此基础上直接估算 出固定成本和单位变动成本的一 种方法。
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例如：

某厂新购入一套热处理设备，电费属于混合 成本，没有历史资料。技术测定显示，该设 备每天使用前需预热，耗电10度；每使用一 小时耗电30度。设电费为0.5元/度。则对这 项成本进行性态分析如下：
Alternative1: y1=5×4000=$20 000 Alternative2: y2=$10 000 Alternative3: y3=$3000+2×4000=11 000 Alternative2 is the least costly.
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在相关范围内，线性成 本函数（单个动因的情 况下）可被一个常数(或 截距a) 和一个斜率系数 （b）表述出来: Y=a +b X
回顾案例

例如：某企业生产甲产品，按财务会计的概念， 程序和方法计算产品成本，本年度7月、8月产品 成本资料如下：
unit DM
7 8 140 000 150 000 700 000 720 000
month
Total costs DL
280 000 280 000
OH
420 000 480 000
$10 000
Intercept 截距
x = phone-minutes used
X
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Alternative3:
y = $3 000 + $2x
y = cost
y
$3 000
x = phone-minutes used
x
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了解成本性态是进行方案选择的 关键因素

Suppose cannon services expects: 4 000 phone-minutes per month Then:

Managers are interested in estimating past cost-behavior functions primarily because these estimates can help them
make more accurate cost predictions about future costs.
一元线性假设
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Variable Costs
Variable costs change in total in proportion to changes in the related level of total activity or volume.
Total Long Distance Telephone Bill
Number of Local Calls
Monthly Basic Telephone Bill per Local Call Number of Local Calls
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Monthly Basic Telephone Bill
Mixed Costs
Mixed costs contain a fixed portion that is incurred even when facility is unused, and a variable portion that increases with usage.
Recognize various approaches to cost estimati..
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is the attempt to measure a past relationship between costs and the level of an activity.
Describe linear cost functions and three common ways in which they behave
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Cost Function... Cost Function is a mathematical
expression describing how costs change with changes in the level of an activity.
通过技术测定把热处理电炉的预热耗电成本(初始量)划归 固定成本，把预热后进行热处理的耗电成本划为变动成本， 因此，以设备工作工时为业务量(x)，则 固定成本部分为： 10×0.5×30=150（元/月） 变动成本部分为： 0.5×30x=15X（元） 该设备每月的电费分解模型为 Y=150+15X 31