CHAPTER 10 Cost–volume–profit analysis 423
Number of times advertisement is aired
Total televisionadvertising cost
Total cost
Fixed cost
9500
10000
11000
12000
$13 000
0 1 2 3 4 5 6
FIGURE 10.3 Mixed cost behaviour
Coconut Plantations Pty Ltd established an online shop to increase sales of its coconut-based pro-
ducts. Jo, the manager, is taking a conservative approach to online selling and is initially only offering
a single product, coconut candles. She is planning to analyse profitability of the online shop before
offering a wider range of products. The following information relating to internet activity and internet
charges was extracted from her accounts and the sales database.
3 months to
31 March 2017
3 months to
30 June 2017
Number of online sales orders
Total internet charges $
5 000
150 000 $
5 500
155 000
Before CVP analysis can be undertaken, we need to split the total costs into their fixed and variable
components. Given our discussion of cost behaviour earlier, we know that fixed costs stay the same
regardless of the level of activity and total variable costs increase in proportion to output. Therefore, the
variable cost behaviour can explain why the costs of Coconut Plantations have increased by $5000 for an
increased activity level of 500 online sales orders. To calculate the variable cost per order we divide the
difference in cost by the difference in activity level as follows.
Change in internet charges
Change in online orders
Variable cost per unit
$5 000
500 online orders
$10 per online order
We know that total costs are equal to total fixed costs plus total variable costs. Therefore, to calculate
the total fixed costs we have to deduct the total variable costs, which will be equal to the number of sales
orders times $10, from the total costs. From the calculations below we have calculated total fixed costs
to be $100 000.
For 5000 online orders = $150 000 − (5000 online sales × $10) = $100 000
For 5500 online orders = $155 000 − (5500 online sales × $10) = $100 000
Coconut Plantations Pty Ltd can now use this cost behaviour knowledge to determine total costs for
any level of online orders within the relevant range. The manager will know that costs will increase at
the rate of $10 per online order due to the variable cost behaviour, and that fixed costs will remain con-
stant at $100 000. For example, if the manager wanted to know the total cost at 5100 online orders, we
would determine the variable cost (5100 × $10) and then add the fixed cost ($100 000), which would
give a total cost of $151 000.