Margin of profit

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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Noun
1. the ratio gross profits divided by net sales
(synonym) profit margin, gross margin
(hypernym) ratio

Gross profit divided by net sales, used to measure a firm's operating efficiency and pricing policies in order to determine how competitive the firm is within the industry.