His Business Was Tough. Diesel Prices Made It Impossible.

Small trucking companies operate vehicles that haul cargo for a fee, charging customers based on distance, weight, or time. A trucker's revenue is fairly predictable—you get paid per mile or per load. But costs fall into two buckets: some stay roughly the same every month (truck payments, insurance, rent on a garage), while others climb whenever fuel prices rise or the truck rolls more miles. Diesel fuel is the classic variable cost—the more miles you drive, the more fuel you burn and the more you pay. This article focuses on truckers with tight profit margins—meaning the gap between what they earn and what they spend is small. When diesel prices soar, that variable cost eats into profit fast, and if a trucker can't raise rates quickly enough or cut routes, the business can slip into loss or bankruptcy.

• Diesel fuel rises with every mile driven, making it a variable cost; truck loan payments stay the same monthly, making them fixed costs.
• Small truckers with thin margins have little room between revenue and total costs, so a spike in variable costs can turn profit into loss.
• When diesel prices surge, the trucker must decide what information (current fuel price, route volume, customer rates, fixed loan amount) is relevant to staying profitable.
• Fixed costs don't change when miles drop, but revenue does—so high fixed costs plus falling miles or rising variable costs creates a profitability crisis.

Variable cost

A cost that changes in total as the level of business activity (like miles driven or units sold) goes up or down; diesel fuel for a truck is variable because you buy more as you drive more.

Fixed cost

A cost that stays roughly the same in total each month or year, no matter how much activity the business does; a truck loan payment is fixed because you pay the same amount each month regardless of miles driven.

Mixed cost

A cost that has both a fixed component and a variable component; for example, a phone bill with a base monthly fee plus charges for extra data usage.

Operating leverage

The effect of fixed costs on profit: when sales are high, fixed costs are spread across many units so profit grows fast; when sales drop, those same fixed costs eat up more of each sale, and profit shrinks quickly.

Margin

The difference between revenue and total costs; a 'thin margin' means the gap is small, leaving little cushion if costs rise or revenue falls.

Relevant information

Facts about future costs and revenues that differ depending on which decision a manager makes; information that wouldn't change the decision is irrelevant, even if it's true.

1. 01

   In the article, which trucker costs stay the same whether the truck runs 500 or 5,000 miles that month—and which ones climb with the miles?

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   Answer: Students should identify that truck loan payments, insurance, and garage rent are fixed (they don't change with miles), while diesel fuel is variable (it rises as miles rise). Some may note mixed costs like maintenance (has a base wear-and-tear component plus mileage-driven component). The key is recognizing the behavior pattern, not the cost name.
2. 02

   If diesel fuel is a variable cost, explain why a small trucker operating 'with little margin for error' faces a bigger profit crisis from a fuel-price spike than a large fleet operator might.

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   Answer: Small truckers with thin margins have little buffer. A fuel-price spike immediately compresses the gap between revenue and total costs—on a 3% margin, a 10% fuel cost jump can wipe out or eliminate profit. Larger fleets can absorb spikes by spreading fixed costs across more trucks and often negotiate better fuel prices; small operators cannot. The fixed costs (truck loan) don't shrink when fuel spikes, amplifying the crisis (operating leverage).
3. 03

   Suppose a trucker faces a choice: raise customer rates or cut unprofitable routes. What information about fixed costs, variable costs, and future revenue would be relevant to that decision?

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   Answer: Relevant information includes: the trucker's current profit per mile at today's fuel prices, the size of the fixed costs the trucker must cover (loan payments), and the customer demand for the routes under consideration. Irrelevant: the truck's original purchase price (sunk cost) or what competitors paid for their trucks. The trucker should cut a route if revenue from that route won't cover the variable costs of running it—and once routes are evaluated, only forward-looking data matters.
4. 04

   How would a trucker's break-even point (the number of miles needed to cover all costs) shift if diesel prices doubled—and what does that tell you about the relationship between variable costs and profitability?

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   Answer: As diesel prices rise, each mile delivers less profit (variable cost climbs), so the trucker must drive MORE miles to reach the point where total revenue equals total costs. The break-even point moves right (higher miles needed). This shows operating leverage: fixed costs become harder to cover when variable costs rise, and the trucker is squeezed unless volume or revenue per mile increases.

Open by drawing two columns on the board: 'Fixed' and 'Variable.' Ask students to list trucking costs—then classify them together. Highlight the truck loan ($1,200/month no matter what) vs. diesel ($3 per gallon × miles). Draw a simple profit bar (Revenue minus Fixed Costs minus Variable Costs) and show how sliding the diesel cost up shrinks that bar fast—especially for a trucker with thin margins. Anchor the discussion with a concrete number from the article (if it cites fuel price or a bankruptcy case) to make the squeeze real. End by asking: 'If you owned this trucking company, what one piece of information would you need today to decide whether to keep going or fold?'