Net Profit Margin = Net Income ÷ Revenue
The Short Version
Growth and profitability trends matter as much as any single-period number. Analysts track revenue growth (is the top line expanding?) alongside margins (how much of each sales dollar turns into actual profit) to see whether a business is scaling efficiently or just growing without becoming more profitable.
Explain It Like I'm 10
Imagine a kid's snow-cone stand sold $100 worth of snow cones this summer (that's revenue), but the ice, cups, and syrup cost $70, leaving $30 in actual profit. That $30 is 30% of the $100 sold — that's the 'profit margin.' Now imagine next summer sales double to $200, but the profit only grows to $40 (20% margin) because costs got out of hand. Sales are UP, but the business is actually becoming LESS efficient at turning sales into real profit — that's exactly the kind of pattern analysts watch for.
Step-by-Step Example
- 1 Year 1: Revenue = $100, Net Income = $30 → margin = 30%.
- 2 Year 2: Revenue = $200 (up 100%!), Net Income = $40 → margin = 20%.
- 3 Revenue growth alone looks great: it doubled.
- 4 But margin fell from 30% to 20% — profit only grew 33% ($30 to $40), far slower than sales.
- 5 The lesson: always check margin trends alongside revenue growth — fast sales growth funded by shrinking profitability can be a warning sign, not just good news.
Quick Recap
- ✓ Gross margin, operating margin, and net margin each strip out different layers of cost — covered in depth in the Accounting guide.
- ✓ Rising revenue with shrinking margins can be a warning sign that growth is coming at the cost of profitability.