Net Profit Margin

Profit margin, Net Margin or Net Profit Ratio all refer to a measure of profitability. It is calculated using a formula and written as a percentage or a number.Margin is mostly used for internal comparison. It is difficult to compare accurately the net profit ratio for different entities. Individual business' operating and financing arrangements vary so much that entities are bound to have different levels of expenditure, that comparison of one with another can have little meaning.
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Net income divided by sales; the amount of each sales dollar left over after all expenses have been paid.

same as net margin.