Correction
A subtotal name tells you where to look. It does not, by itself, tell you that two companies included the same kinds of costs. To compare gross profit or operating income, inspect the lines and notes behind each amount.
Why the mistake can seem reasonable
Both statements may print gross profit or operating income in bold. A table of margins can then make the numbers look directly comparable. But the same label can sit above or below different expense lines.
Compare what the subtotals include
Sable Ridge sells manufactured instruments and installation services. Its cost-of-revenue line includes costs of both. A manufacturer that sells only products may report cost of goods sold. A professional service company may report the costs of providing services under another name. Before comparing their gross profit rates, check what each company counted as customer revenue and as the related cost.
For operating income, check where each company places selling, administrative, research, and other material costs. If one company puts a cost above operating income and the other puts a similar cost below it, their reported subtotals answer different questions. The notes may give enough detail to make an adjusted comparison. If they do not, say what difference remains instead of claiming the margins are equivalent.
Quick checkTwo companies both report operating income. Is the matching label enough to conclude that one has a higher operating margin on the same basis?
Answer: No. Divide each operating-income amount by that company's revenue, then check the costs and accounting policies included in each subtotal. A matching name alone does not establish a common basis.
When this mistake may appear
- Two companies both report gross profit or operating income.
- A company's statement changes the line used for a cost.
Your work may contain this mistake if:
- You compare two margins without checking which costs are included.
- You assume the same line name means the same accounting treatment.