Northlake’s season as fixed + variable per skier-day × skier-days
◈ 6 cardsSort a company’s cost list into fixed, variable and mixed, sum the fixed and variable-per-unit parts into one cost equation, and predict total cost at a volume inside the range.
Ten costs, two numbers
Northlake Nordic Centre Inc.'s season has ten cost lines. Sorted by behaviour, they collapse into two figures — a variable cost per skier-day and a fixed cost for the season — and those two figures are the whole of what Module 10 needs.
| Cost | Behaviour | Per skier-day | For the season |
|---|---|---|---|
| Groomer fuel | variable | 3.00 | |
| Café supplies | variable | 2.50 | |
| Rental-ski maintenance | variable | 1.50 | |
| Trail-pass printing and card fees | variable | 2.00 | |
| Variable cost per skier-day | 9.00 | ||
| Lodge lease | fixed | 96,000 | |
| Salaried staff | fixed | 118,000 | |
| Amortization, groomer and lodge | fixed | 41,000 | |
| Insurance | fixed | 18,000 | |
| Loan interest | fixed | 24,000 | |
| Advertising | fixed | 18,000 | |
| Fixed costs for the season | 315,000 |
The sort is the skill. Salaried staff are fixed although they are paid monthly — the pay date is not the behaviour; what matters is that the payroll does not move with skier-days. Amortization is fixed because Northlake uses straight-line (Module 11 will show units-of-production, which would make it variable). Advertising is fixed because it is a budget set before the season, not a cost incurred per skier. And a mixed cost such as hydro, once separated (L9.4), contributes its fixed part to one total and its variable part to the other.
The cost equation
At 18,000 skier-days: 315,000 + 162,000 = 477,000. At 25,000: 315,000 + 225,000 = 540,000. Both are inside the relevant range of 10,000–30,000, so the straight line can be trusted. In a spreadsheet the equation is one cell — =315000 + 9*B2 — and the same cell answers every "what if" the owner asks.
Why not read it off the income statement?
Because the ASPE income statement sorts by function. Its line Trail and lodge operations 330,000 contains the groomer fuel (variable), the lodge lease (fixed) and the patrol (step) all added together; Administration 165,000 mixes salaried staff with card fees. No line on the functional statement is purely fixed or purely variable, so the two parts of the equation cannot be extracted from it. They come from the cost list — the ledger detail behind the statement — which is why a case gives you the list.
A second business — Cedar Ridge Golf Club Ltd.
Rounds played is the driver. Cart fuel 2.40 a round and range balls 0.60 a round are variable: 3.00 per round. The greens crew at 210,000 salaried, the course lease 90,000 and clubhouse amortization 35,000 are fixed: 335,000. Total cost = 335,000 + 3 × rounds, so 30,000 rounds cost 335,000 + 90,000 = 425,000. Different business, same two numbers, same equation.