Which of the following is not a profitability ratio?

Proprietary Ratio is not a profitability ratio.

Proprietary Ratio is a solvency ratio that measures the relationship between proprietor's funds and total assets.

Formula: Proprietary Ratio = $\frac{\text{Proprietor's Funds}}{\text{Total Assets}} \times 100$

It indicates what portion of total assets is financed by the proprietors (owners). This ratio assesses the long-term financial position and solvency of the business.

The other three options are profitability ratios:

Price Earning Ratio: Though sometimes classified as a market ratio, it is based on earnings (profit) and shows how much investors are willing to pay per rupee of earnings.

Earnings per Share: Shows the profit available to equity shareholders per share. It directly measures profitability from shareholder perspective.

Operating Ratio: Expresses the relationship between operating costs (cost of goods sold + operating expenses) and net sales. A lower operating ratio indicates better profitability. Formula: $\frac{\text{Cost of Goods Sold + Operating Expenses}}{\text{Net Sales}} \times 100$