Gross profit margin: Gross profit x $100/$Total sales $=$ x $\%$ Operating margin $($EBIT or Profit before Interest and Tax$)$: Operating profit x $100/$Total sales $=$ x $\%$ EBITDA $($Earnings or Profit before interest tax and depreciation and amortisation$)$ margin: EBITDA x $100/$Total sales $=$ x $\%$ Net profit margin: Net profit after tax x $100/$Total sales $=$ x $\%$ Return on Assets: Net profit after tax x $100/$Total assets $=$ x $\%$ Return on Equity: Net profit after tax x $100/$Total equity $=$ x $\%$