With relation to volume of production during the period, the costs may be Fixed or Variable.
Fixed Costs
Are those that are not dependent on the volume of production during the period, i.e., these costs do not change irrespective of the quantity produced.
Thus, whether a company produces one unit or ten units of one or more products per month does not matter, because the fixed costs remain the same.
Examples:
Factory rent
Depreciation of machines
Salaries and social contributions for factory supervision
The fixed costs are related to the indirect production costs because they are not proportional to the quantities of the finished products.
Variable Costs
Are those that vary with the quantities produced, as in the case of raw material.
Variable costs are directly related to Direct Manufacturing Costs.
Semi-fixed Costs
Are the Fixed Costs that have a variable portion. The fixed installment is independent of the production during the period.
Example:
Electricity for factory lighting.
Semi-variable Costs
Are the variable costs that have a fixed portion.
Example:
Labor applied directly to production (because it varies with the quantities produced).