Operating expenses are often allocated differently in financial accounting than in cost accounting. If, for example, an expense incurred in external accounting covers a whole year, you must assign a proportion of the whole to each individual cost accounting period. You distribute irregularly-occurring expenses, according to cost-origin, on the months in which they are incurred. This allows you to avoid irregularities within cost accounting. Costs allocated in this manner are termed accrued costs.

The even distribution of a one-off expense is referred to as time-based accrual calculation. With the aid of the accrual calculation functions, you can take these costs into account in the Controlling component.