What it means
CVP analysis rests on a simple split of costs into fixed costs, which do not change with volume, and variable costs, which rise with each unit sold. Once costs are split this way, profit becomes a straightforward function of how many units are sold and at what price.
The central measure is the contribution margin, which is the selling price per unit minus the variable cost per unit. Each unit sold contributes that amount towards covering fixed costs, and once fixed costs are covered, every extra unit adds to profit.
The break-even point is the volume at which total contribution equals total fixed costs, so profit is zero. It can be stated in units or in sales dollars, and it tells a manager the minimum performance needed to avoid a loss.
CVP also answers what-if questions, such as what happens to the break-even point if rent rises by $10,000, or how many extra units are needed to pay for a price cut. Analysts can change one assumption at a time and see the effect on profit within seconds, which makes it a favourite tool in budget meetings.
A useful companion is the margin of safety, which is the gap between expected sales and break-even sales. A large margin of safety means sales can fall a long way before the business makes a loss, and a small one means the business is exposed.
The model rests on simplifications, such as a constant selling price, costs that behave in a straight line, and a fixed mix of products. It works best within a normal range of activity, and results should be treated as guides, not forecasts.
Where reality departs a long way from these assumptions, the numbers need to be adjusted by judgement.
In practice
Real-world examples
Example 1
A cafe owner is deciding whether to open a second site with fixed costs of $9,000 a month. The average sale yields $4 of contribution, so the site needs 2,250 sales a month just to break even, and she checks whether the location can deliver that. Footfall counts outside the shop help her judge whether 75 sales a day is realistic.
Example 2
A software firm considers cutting its subscription price from $80 to $70 with variable costs of $20 a customer. The contribution falls from $60 to $50, so it must win about 20% more customers just to earn the same total contribution.
Example 3
A charity running a fundraising dinner has fixed costs of $15,000 for the venue and staging, and variable costs of $40 a guest. With tickets at $100, it needs 15,000 / 60 = 250 guests to break even. Any seats sold beyond that raise money for the cause, so the organisers focus on filling the room.
Think of it
Think of driving a car on a long journey. Fixed costs are like the cost of insurance and road tax that you pay before turning the ignition. Variable costs are like petrol, which goes up the further you drive. Your revenue is the distance covered, and the analysis tells you how many miles you must drive just to pay for the fuel and insurance.
Formula
Calculation
Break-even units = fixed costs / contribution margin per unit
Units for a target profit = (fixed costs + target profit) / contribution margin per unit
A company sells a product at $50 with a variable cost of $30, so the contribution margin is $50 - $30 = $20 per unit. Fixed costs are $240,000 a year. Break-even units = $240,000 / $20 = 12,000 units, which is 12,000 x $50 = $600,000 of sales. To earn a profit of $60,000, units needed = ($240,000 + $60,000) / $20 = $300,000 / $20 = 15,000 units. If expected sales are 18,000 units, the margin of safety is 18,000 - 12,000 = 6,000 units, or 6,000 / 18,000 = 33.3%.Case study
Seen in the real world
Tallowmere Bikes is an illustrative, fictional maker of electric bicycles. It sells each bike for $1,800 with variable costs of $1,200, and its fixed costs are $1,500,000 a year, so the contribution is $600 per bike.
The break-even volume is 2,500 bikes. Management had forecast 3,000 sales, a margin of safety of only 500 bikes, or about 17%, which made the board uneasy about a plan to add a new showroom costing $180,000 a year.
CVP analysis showed that the showroom would raise break-even volume by 300 bikes to 2,800. In this illustrative case, the board approved it only after the sales team provided evidence that the showroom would add at least 600 sales.
Watch out
Common mistakes
- Misclassifying a cost as fixed or variable, which gives the wrong contribution margin and a wrong break-even point.
- Treating the break-even point as a sales forecast, when it is only the minimum volume needed to avoid a loss.
- Using the model outside the normal range of activity, where fixed costs may step up and unit prices may change.
Questions
People also ask
Does CVP analysis work for services?
Yes, using a unit such as a billable hour, a customer or a project, as long as costs can be separated into fixed and variable parts. A consultancy might measure break-even in billable days per year.
How does CVP deal with several products?
It uses a weighted average contribution margin based on the expected sales mix, which assumes the mix stays constant.
Why is CVP useful to non-finance managers?
It turns a business plan into one clear question, which is whether the volume needed to break even is realistic. That question is much easier to debate than a page of forecasts.