关于profit margin

Profit margin = Net profit margin
Gross profit margin毛利率
Profit margin, net margin, net profit margin or net profit ratio all refer to a measure of profitability. It is calculated by finding the net profit as a percentage of the revenue.
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margin是差额,但是这个词组就是利润率的意思.
解释是说,profit margin=net margin=net profit,都是用来计算获利能力的.净利率是指（扣除tax之后的net income/sales)
这些用词是固定短语,如果你要非按字面翻译,那我就没办法解释了.