The Income Statement

The P&L — from top line to bottom line

Every public company publishes three financial statements each quarter: the Income Statement (also called the P&L, or Statement of Income), the Balance Sheet, and the Cash Flow Statement. In this unit, you'll learn to read all three. We start with the P&L because it's the one that moves stock prices.

The Income Statement answers one question: how much did the company earn (or lose) over a period of time? A quarter, a year. It starts with revenue at the top and subtracts layers of cost until you reach net income at the bottom. Each layer peeled away reveals something important about the business.

The structure

Every income statement, from a hot dog stand to Apple, follows this skeleton:

1. Revenue (the "top line") — what customers paid
2. − Cost of Goods Sold (COGS) — direct cost to produce what was sold
3. = Gross Profit — revenue minus COGS
4. − Operating Expenses (R&D, SG&A, D&A) — the cost of running the business
5. = Operating Income (EBIT) — profit from operations
6. − Interest / + Other Income — cost of debt, non-core items
7. = Pre-Tax Income
8. − Taxes
9. = Net Income (the "bottom line") — what's left for shareholders

Each subtraction is a margin gate. Gross margin tells you pricing power. Operating margin tells you operational efficiency. Net margin tells you what actually makes it through.

Explore one

Hover any line item for a plain-English explanation. Toggle "Show margins" to see what percentage of revenue each line represents.

Notice a few things in this fictional Acme Corp:

• Revenue grew every year — that's the easy sell to investors. But look at 2024.
• COGS rose faster than revenue in 2023–24 — gross margin compressed from 58% to 56%. Raw-material costs or pricing pressure? Either way, the business is getting squeezed.
• SG&A jumped in 2024 — from 15% of revenue to 16%. Small-sounding, but on $13.1B in revenue, that's $130M of extra cost.
• Interest expense nearly doubled from 2022 to 2024 — the company took on debt. Combined with the margin compression, EBIT actually fell in 2024. The top line grew; the bottom line shrank.
• Net income peaked in 2023 and declined in 2024. The income statement tells you why in each layer.

This is the fundamental skill: don't just read net income — read the layers above it.

The three margins

Gross margin is about pricing power and input costs. A software company might have 80% gross margin (no physical goods). A grocery chain might run at 25%.

Operating margin is about how well the company controls its overhead. Two companies with identical gross margins can have wildly different operating margins if one over-hires and the other doesn't.

Net margin is the final answer, but it's contaminated by non-operating items (one-time gains, interest, tax timing). Operating margin is usually the cleaner read.

Drag the sliders. The waterfall makes margins visceral — watch how a small increase in COGS cascades through every line below it.

EBITDA — the metric Wall Street loves (and abuses)

You'll hear "EBITDA" constantly. It stands for Earnings Before Interest, Taxes, Depreciation, and Amortization:

The logic: D&A is a non-cash charge that reflects past capital spending. Stripping it gives you a "cash earnings" proxy. It's useful for comparing companies with different capital structures and depreciation schedules.

The problem: some companies lean on EBITDA to hide the fact that they need massive ongoing capital investment just to stay in business. If a factory needs $500M of capex every year and D&A is $400M, EBITDA looks great but the business is barely generating free cash. Always check capex alongside EBITDA. The Cash Flow Statement (next unit) makes this explicit.

Warren Buffett's skepticism applies here: depreciation represents a real economic cost — the wearing out of assets. Ignoring it in your headline metric doesn't make it disappear.

Revenue recognition — where the games begin

Schilit's first two shenanigans are about revenue:

EM Shenanigan No. 1: Recording Revenue Too Soon. Companies accelerate the recognition of legitimate revenue — shipping product early, changing terms, using percentage-of-completion accounting aggressively.

EM Shenanigan No. 2: Recording Bogus Revenue. Fabricating revenue out of thin air. Round-trip transactions, recording loans as revenue, counting gross merchandise volume as revenue when you're just the middleman.

The Enron case is the canonical example. Schilit documents:

In just five short years, Enron's revenue had miraculously increased by an astounding factor of 10 (rising from $9.2 billion in 1995 to $100.8 billion in 2000). Curious investors might have questioned how frequently companies tend to grow their revenue from under $10 billion to over $100 billion in five years. The answer: never. — Financial Shenanigans

And the critical red flag:

Even though Enron made the list with the big boys, its reported profits, totaling less than 1 percent of sales, paled in comparison to the others. Moreover, profits never grew proportionally with sales.

Revenue that grows 10× while profit barely moves is the reddest of red flags.

Spot the shenanigan

This interactive walks you through five real-world-inspired scenarios. For each one, decide: red flag or healthy?

Schilit's universal message:

Smart investors would do well to maintain a healthy skepticism and perform rigorous due diligence with regard to financial reports. — Financial Shenanigans

Quick check

What you now know

• The income statement flows Revenue → Gross Profit → EBIT → Net Income, each subtraction a margin gate.
• Gross margin = pricing power. Operating margin = operational efficiency. Net margin = final answer (but noisy).
• Revenue growth without profit growth is the reddest flag in accounting.
• Schilit's seven Earnings Manipulation Shenanigans all target the income statement — from recording revenue too soon to hiding expenses on the balance sheet.
• EBITDA is useful but incomplete — always pair it with capex to see the full picture.
• Never trust the bottom line alone. Read the layers.

Next: The Balance Sheet — assets, liabilities, equity, and the accounting identity.