The concept of cost? More than forty ~

Management accounting is a new discipline developed by absorbing modern scientific management methods on the basis of financial accounting. On the one hand, it is the extension and development of financial accounting content; On the other hand, it is also the application of some methods of modern scientific management in accounting, including: cost-volume-profit analysis, business forecasting and decision-making, investment decision-making, comprehensive budget, cost and inventory control, business performance assessment, etc.

In the process of forecasting, decision-making, planning, control and assessment of enterprise production and operation activities by using the above methods, management accounting can not only use the specific cost concepts adopted by financial accounting, but also use various cost concepts according to different needs.

1, variable cost and fixed cost

This is the concept of cost divided according to cost habits. The so-called cost habit refers to the total cost and business.

Dependence of total quantity (output or sales volume). Any change in total cost is directly proportional to the change in total business volume, which is called variable cost, such as material cost; Where the total cost is fixed without being affected by the change of business volume, it is called fixed cost, such as depreciation expense and salary of management personnel.

It must be noted that "variable" and "fixed" of variable cost and fixed cost refer to the sum of variable cost and fixed cost. If it refers to unit cost, it is just the opposite, that is, the variable cost of unit product remains unchanged, but the fixed cost of unit product changes inversely with the increase or decrease of business volume, that is to say, the greater the business volume, the less the fixed cost of unit. The product cost formula consisting of variable cost and fixed cost can be expressed as:

Y=a+bx where: y = total cost a= total fixed cost.

B= variable cost per unit product x= business volume

It should also be noted that in practical work, many detailed projects have both variable costs and fixed costs, so they are collectively called "mixed costs" (such as maintenance costs) and can be divided into three categories: variable costs, semi-fixed costs and deferred variable costs.

2. Cash cost and input cost

The cost to be paid refers to the cost of cash and other working capital, such as materials consumed and wages paid; Immersion cost refers to the cost that has been paid in the past and cannot be changed when making decisions at present, such as depreciation expense.

3. Historical cost and replacement cost

Historical cost refers to the actual cost that has occurred; Replacement cost refers to the cost of purchasing the same assets from the market at present.

4. Deferred costs and non-deferred costs

Deferred costs mean that enterprises are limited by financial resources. Under the premise of not affecting the overall situation, postpone the implementation of the selected scheme and choose the expenses related to the scheme; On the contrary, when it will affect the whole situation, it is called non-deferrable cost.

5. Controllable costs and uncontrollable costs

Controllable cost refers to the cost that an assessment unit (workshop, department) can control and be responsible for; Uncontrollable cost refers to the cost that cannot be controlled and responsible.

6. Avoidable costs and unavoidable costs

Avoidable cost refers to the part of the cost that can be avoided being included in the total cost of the scheme because of changing the scheme decision; On the contrary, it is an inevitable cost.

7. Marginal cost and differential cost

Marginal cost refers to the increased or decreased cost when producing more or less one product; Differential cost is the difference when comparing two schemes.

8. Opportunity cost and estimated cost

Opportunity cost refers to the potential income or income lost when choosing an optimal scheme from various alternatives and giving up the suboptimal scheme, that is, the price paid for choosing this scheme; Estimated cost refers to the opportunity cost that can only be determined by estimation and calculation, and it is a special form of opportunity cost.

9. Dedicated costs are the same as * * * costs.

Special cost refers to the cost that can be clearly attributed to a certain type, batch or department; * * * The same cost refers to the cost that needs to be shared by several batches or relevant departments.

10, related costs and unrelated costs

Related costs refer to various forms of future costs related to decision-making, including variable costs, fixed costs, cash costs, replacement costs, differential costs, marginal costs, opportunity costs, estimated costs, controllable costs, avoidable costs, deferrable costs and special costs. Irrelevant costs refer to costs that have occurred in the past or have not yet occurred, but have no impact on future decisions, including the aforementioned immersion costs, historical costs, uncontrollable costs, inevitable costs, non-deferred costs and * * * same costs.

In addition, there are other cost concepts in management accounting, such as discretionary fixed cost, committed fixed cost, step-by-step variable cost, adjustment preparation cost, out-of-stock cost, divisible cost, accrued cost, target cost and capital cost.