Cost Behaviors

What is cost behavior?

A term used to describe how costs change or react to changes in the volume of activity

What are the three classifications of costs in cost behavior analysis?

Variable costs, fixed costs, and mixed costs.

How do variable costs behave in total versus per unit?

Variable costs in total change in direct proportion to changes in the volume of activity, while variable costs per unit remain constant and do not change.

What are examples of variable costs?

Direct materials and direct labor.

How do fixed costs behave in total versus per unit?

Fixed costs in total are constant and do not change when the volume of activity changes, while fixed costs per unit change inversely as activity volume increases.

What are examples of fixed costs?

Depreciation, rent, and advertising.

What is a mixed cost?

A cost containing both a variable element and a fixed element, meaning neither its total cost nor unit cost is constant.

What are examples of mixed costs?

Utilities and overhead.

What is the relevant range?

The range of activity within which the assumptions made about cost behaviors by managers are valid.

What shape do cost behavior patterns assume within the relevant range?

They are assumed to be linear, plotting as a straight line within the relevant range.

Why are cost behavior ideas useful in management decision-making?

They allow managers to develop expectations of costs at any level of activity.

Which cost measures should managers utilize when working with cost behavior analysis?

Variable costs expressed on a per unit basis and fixed costs in total, because both are considered constant at all activity levels.

What is the problem with mixed costs in cost behavior analysis?

They do not have a constant component because they contain both fixed and variable elements.

What is the method used to separate a mixed cost into its fixed and variable components?

The High-Low Method.

How do you choose the two data points when using the high-low method?

Choose them based on the high and low activity level (never choose them based on the high and low cost).

What is the formula to calculate variable cost per unit in step 2 of the high-low method?

(Cost at high activity level minus Cost at low activity level) divided by (High activity level units minus Low activity level units).

How do you solve for total fixed cost in step 3 of the high-low method?

Plug either the high or low activity point's total cost and units into the cost formula (Total Cost = Fixed Cost + Variable Cost) and solve for F.

What is the final cost formula structure derived from the high-low method?

Total Cost = Total Fixed Cost + Variable Cost per Unit * x), where x represents activity (such as units produced).

What is the structure of a traditional income statement?

Sales Revenue minus Cost of Goods Sold equals Gross Profit, minus Other Expenses equals Net Income.

How are expenses classified on a traditional income statement?

By function.

Is the traditional income statement used for internal decision-making?

No, managers prefer to classify expenses by cost behavior instead.

What is the structure of a contribution income statement?

Sales Revenue minus Variable Costs equals Contribution Margin, minus Fixed Costs equals Net Income.

How are expenses classified on a contribution income statement?

By cost behavior pattern.

What does contribution margin represent?

The amount of revenue available to pay (cover) fixed costs and contribute toward a profit.

Why do variable costs and contribution margin increase proportionately when revenues increase?

Because variable costs are a direct function of the level of revenue-generating activity, whereas fixed costs remain constant.

How are utility costs classified and calculated in this analysis?

As a variable cost, calculated as constant per unit ($0.80 per unit), so total utility cost equals units produced multiplied by $0.80.

How are supervisory salaries classified?

As a fixed cost, remaining constant in total regardless of the number of units produced in a month ($21,000 per month).

How do you solve for an unknown cost (such as maintenance) when given total overhead and other known cost components?

Subtract the known variable and fixed cost components from the total overhead cost to isolate the unknown cost.

How do you break down a mixed maintenance cost into its fixed and variable parts using data points?

Apply the high-low method to calculate the variable cost per unit change and then solve for total fixed costs using either the high or low activity point.

How do you express a combined total overhead cost formula with multiple overhead components?

Combine all individual variable components (e.g., $0.80X + $1.60X) and fixed components (e.g., $21,000 + $9,000) into a single overarching formula (e.g., Total Overhead = $2.40X + $30,000).

What is the key difference between how expenses are listed on a traditional income statement versus a contribution income statement?

Traditional income statements classify expenses by function (resulting in gross profit), whereas contribution income statements classify expenses strictly by cost behavior pattern (separating total variable costs and total fixed costs to arrive at contribution margin).