Net margin is net income as a percentage of revenue: how much of each dollar of sales ends up as profit for shareholders after every cost, interest and tax.
Formula
net margin = net income / revenue
Both figures are for the same period, as reported. Net income here is the figure attributable to the company's shareholders. A trailing twelve-month margin divides TTM net income by TTM revenue.
Reading it
Net margin is the noisiest of the three margins, because net income carries tax effects, investment gains and losses, and one-off items. A jump in net margin with a flat operating margin usually comes from below the operating line. Check the income statement before drawing a conclusion.
When it says "not reported"
- Net income is not reported for the period.
- Revenue is not reported, or is zero.