The operating profit margin, also known as the operating margin, is a financial metric that represents the proportion of a company's operating income to its net sales. It reflects the profitability of a company's core operations before taking into account non-operating items like interest income and expenses. Here's the formula to calculate the operating profit margin:

Operating Profit Margin = (Operating Income / Net Sales) * 100

Where: - Operating Income: This is the revenue generated from regular business operations after subtracting the costs directly related to those operations (COGS, operating expenses, etc.), but before accounting for non-operating items such as interest income, interest expenses, and taxes. - Net Sales: This refers to the total sales revenue from the primary business activities of the company, excluding any non-operating revenues.

To calculate this ratio, you'll need the following data from the income statement: 1. Operating Income: This is the revenue left over after paying for direct and indirect costs associated with generating the sales, but before considering any non-operating items. 2. Net Sales: This is the total sales revenue minus any returns, discounts, and allowances.

Once you have the necessary figures, you can calculate the operating profit margin using the formula mentioned above.