• fixed costs - A cost that does not change with an increase or decrease in the amount of goods or services produced. Fixed costs are expenses that have to be paid by a company, independent of any business activity. It is one of the two components of the total cost of a good or service, along with variable cost.

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• marginal costs - The change in total cost that comes from making or producing one additional item. The purpose of analyzing marginal cost is to determine at what point an organization can achieve economies of scale. The calculation is most often used among manufacturers as a means of isolating an optimum production level.