1. What Is an Income Statement?
The income statement — also called the profit and loss statement (P&L) — answers the most fundamental question about a business: Is this company making money?
While the balance sheet shows what a company owns and owes at a single point in time, the income statement covers a period — typically a quarter or a year — and shows how much the company earned, what it spent, and what was left over as profit.
Think of the balance sheet as a photograph and the income statement as a video. The photo tells you where things stand; the video tells you how the story unfolded.
2. The Structure: From Revenue to Net Income
Every income statement follows the same cascading structure, starting broad and narrowing down:
Each level strips away another layer of costs, revealing increasingly specific measures of profitability. Understanding each layer helps you diagnose exactly where a company is strong or struggling.
3. Revenue (Top Line)
Revenue — also called sales or top line — is the total amount of money a company brings in from selling its products or services before any expenses are deducted. It's the starting point of the entire income statement.
Revenue growth is one of the most watched metrics on Wall Street. A company can cut costs to improve profits temporarily, but sustainable growth ultimately requires growing revenue. Watch for:
- •Year-over-year growth rate: Is revenue increasing faster than inflation and the industry average?
- •Organic vs. acquisitive growth: Did revenue grow because the company sold more, or because it bought another company?
- •Revenue concentration: Does 80% of revenue come from one product or customer? That's a risk.
Why it matters: Revenue is the fuel that drives everything else on the income statement. Without revenue growth, a company must rely on cost-cutting to improve earnings — a strategy with natural limits.
4. Cost of Goods Sold and Gross Profit
COGS includes the direct costs of producing goods or delivering services: raw materials, manufacturing labor, factory overhead. For a software company, COGS might include server costs and licensing fees. For a retailer, it's the wholesale cost of merchandise.
Gross profit tells you how much money is left after paying for the core product. The gross margin (gross profit ÷ revenue) reveals pricing power and production efficiency:
- •Software companies often have gross margins of 70–85% — code costs almost nothing to reproduce.
- •Retailers typically have margins of 25–40% — they must buy inventory.
- •Grocery stores run on razor-thin margins of 2–5%.
5. Operating Expenses and Operating Income
Operating expenses (OpEx) are the costs of running the business beyond production. They typically include:
- •Selling, General & Administrative (SG&A): Marketing, salaries, rent, office supplies, management compensation.
- •Research & Development (R&D): Spending on innovation and new products. Tech and pharma companies invest heavily here.
- •Depreciation & Amortization (D&A): Spreading the cost of long-term assets (factories, patents) over their useful life.
Operating income (also called EBIT — Earnings Before Interest and Taxes) shows how profitable the core business is, independent of how it's financed or taxed. This is the best measure of operational performance.
6. Net Income (Bottom Line)
Net income is what's left after all expenses — including interest on debt, income taxes, and one-time items. It's the "bottom line" and the number used to calculate Earnings Per Share (EPS):
EPS is the single number that drives the P/E ratio and is central to Graham's Fair Value formula. When analysts talk about companies "beating earnings," they mean actual EPS exceeded the estimate.
Watch out: Net income can be distorted by one-time gains (selling an asset) or charges (restructuring costs). Always look at recurring net income — the profit the company generates from its ongoing operations — for a clearer picture.
7. The Three Margins Every Investor Should Know
Margins convert raw dollar figures into percentages, making it easy to compare companies of different sizes:
Gross Margin
Gross Profit ÷ Revenue
Measures production efficiency and pricing power.
Operating Margin
Operating Income ÷ Revenue
Measures how well the company manages all operating costs.
Net Margin
Net Income ÷ Revenue
The ultimate profitability measure — what's left after everything.
Expanding margins over time are a bullish signal — the company is becoming more efficient. Shrinking margins might mean rising costs, pricing pressure, or a competitive threat. Track margins over 3–5 years, not just one quarter.
8. What Is EBITDA and Why It Matters
EBITDA (Earnings Before Interest, Taxes, Depreciation, and Amortization) strips out non-cash charges and financing decisions to focus purely on cash-generating ability. It's widely used because:
- •It eliminates accounting differences between companies (different depreciation methods, tax jurisdictions).
- •It's a rough proxy for operating cash flow — how much cash the business generates.
- •It's the basis for the EV/EBITDA ratio, a favorite valuation metric of professional investors and M&A analysts.
Criticism: Warren Buffett has famously called EBITDA a misleading metric because it ignores the very real cost of capital expenditures. A factory needs maintenance whether or not you depreciate it on paper. Use EBITDA as one tool among many, not the only one.
9. Red Flags to Watch For
Revenue growing but profits shrinking
This means costs are rising faster than sales — the company may be buying growth at the expense of profitability, or facing margin compression from competitors.
SG&A growing faster than revenue
If a company is spending disproportionately more on sales and admin to generate each dollar of revenue, it's becoming less efficient — a warning sign of operational bloat.
Frequent "one-time" charges
If a company reports restructuring charges or write-downs every year, those costs aren't really one-time. Management may be using them to make regular earnings look better than they are.
Net income positive but operating cash flow negative
This is a classic accounting red flag. Profits should eventually convert to cash. If they don't, the company may be using aggressive revenue recognition or building up uncollectible receivables.
10. Using the Income Statement on WIT
Every stock detail page on WIT includes multi-year income statement data. Here's how to use it effectively:
- Open any stock page from the dashboard and scroll to the Financial Statements section.
- Check revenue trends — look for consistent year-over-year growth over 3–5 years.
- Compare gross margin year over year — is it stable, expanding, or compressing?
- Look at operating income — this tells you how profitable the core business is, before interest and taxes.
- Cross-reference with the balance sheet — a profitable company with mounting debt may be less attractive than the income statement alone suggests.
- Check the P/E ratio in fundamentals — it's calculated directly from net income (EPS).