By definition, there are no fixed costs in the long run, because the long run is a sufficient period of time for all short-run fixed inputs to become variable. Investments in facilities, equipment, and the basic organization that cannot be significantly reduced in a short period of time are referred to as committed fixed costs. Discretionary fixed costs usually arise from annual decisions by management to spend on certain fixed cost items. Examples of discretionary costs are advertising, insurance premia, machine maintenance, and research & development expenditures. Discretionary fixed costs can be expensive. In economics, the most commonly spoken about fixed costs are those that have to do with capital. Capital can be the fixed price for buying a warehouse for production, machines (which can be paid once at the beginning and not depend on quantity or time of production), and it can be a certain total for the salaries of a certain quantity of unskilled labor. Many things are included in fixed costs depending on the product and market - some firms may decide to hold some resources at fixed rates that other companies may not - but these unexpected or predictable short term fixed costs can be the reason a firm doesn't enter the market (if the costs are too high). These costs and variable costs have to be taken into account when a firm wants to determine if they can enter a market. In business planning and management accounting, usage of the terms fixed costs, variable costs and others will often differ from usage in economics, and may depend on the context. Some cost accounting practices such as activity-based costing will allocate fixed costs to business activities for profitability measures. This can simplify decision-making, but can be confusing and controversial. In accounting terminology, fixed costs will broadly include almost all costs (expenses) which are not included in cost of goods sold, and variable costs are those captured in costs of goods sold under the variable costing method. Under full (absorption) costing fixed costs will be included in both the cost of goods sold and in the operating expenses. The implicit assumption required to make the equivalence between the accounting and economics terminology is that the accounting period is equal to the period in which fixed costs do not vary in relation to production. In practice, this equivalence does not always hold, and depending on the period under