Relevant Range: Videos & Practice Problems
Relevant Range is the range of activity levels where costs behave the way managers normally expect: fixed costs stay fixed, and variable cost per unit remains constant. Within a relevant range, standard cost assumptions are reliable, but outside that range, cost behavior can change. This matters because a cost that seems fixed or variable may shift once activity passes a specific break point.
Relevant ranges often appear when capacity limits, contract terms, or pricing rules create changes in cost behavior. A fixed cost may stay unchanged only up to a certain activity level, then jump to a new fixed amount. In other cases, a cost may be fixed in one range and variable in another, or the variable rate may change across ranges. In general, when a cost graph shows a break or change in slope, it indicates multiple relevant ranges and a need to monitor activity levels near those thresholds.
Relevant Range
Relevant Range
AI Megacomputer Co. negotiates a deal with the local utility company to provide them with 1 million kWh per month. Their contract stipulates that if AI Megacomputer Co. uses more than 1 million kWh in a month they will pay a variable rate of \$0.30 per kWh. How many relevant ranges does AI Megacomputer Co. have in measuring their electricity use, and why?
One: A single contract specifies all the business’ costs, so there is only one relevant range.
One: Since the rate is \$0.30 per kWh, it is irrelevant whether they pay for some of this cost in advance.
Two: Since the cost is fixed below 1 million kWh and variable above 1 million kWh there are 2 relevant ranges.
Three: AI Megacomputer Co. has a relevant range when they use no power, another when they use 0-1 million kWh and a third when they use more than 1 million kWh.
Here's what students ask on this topic:
Relevant range in managerial accounting refers to the specific range of activity levels where cost behavior assumptions hold true. Within this range, fixed costs remain constant, and variable costs per unit stay the same. Outside the relevant range, these cost behaviors can change. For example, a fixed cost might increase if production exceeds a certain capacity, or variable costs per unit might shift due to discounts or contract terms. Understanding the relevant range helps managers predict costs accurately and make better decisions based on expected activity levels.
Within the relevant range, fixed costs remain constant regardless of changes in activity level. This means that whether production increases or decreases, the total fixed cost does not change. However, outside the relevant range, fixed costs can change or 'step up.' For example, if a company’s production exceeds the capacity of one machine, it may need to purchase an additional machine, causing fixed costs to increase. This shift creates multiple relevant ranges, each with its own fixed cost level. Recognizing these ranges is crucial for accurate cost planning and budgeting.
Understanding relevant range is important because it ensures that cost predictions and analyses are accurate. Cost behaviors such as fixed and variable costs are only predictable within the relevant range. If a company operates outside this range, costs may change unexpectedly, leading to inaccurate budgeting and decision-making. For example, variable costs per unit might decrease due to bulk discounts, or fixed costs might increase due to capacity expansion. By knowing the relevant range, managers can better anticipate cost changes and avoid surprises in financial planning.
Yes, variable costs per unit can change outside the relevant range. For instance, a company buying screws might pay 3 cents per screw for up to 5,000 screws, but if they purchase more than 5,000, the price per screw might drop to 2 cents due to bulk discounts. This change in variable cost per unit creates a new relevant range. Understanding this helps managers anticipate cost savings or increases when production volume changes significantly.
Real-world examples of relevant ranges include server capacity for a web app, legal retainers, and bulk purchasing discounts. For example, a server can handle up to 1,500 requests per second at a fixed cost, but if requests exceed this, a second server is needed, increasing fixed costs. Similarly, a legal retainer might cover 100 hours of work at a fixed cost, but additional hours are billed hourly, changing cost behavior. Bulk discounts on materials, like screws, can reduce variable costs per unit after a certain quantity. These examples illustrate how costs can shift at breakpoints, defining multiple relevant ranges.
