Table of Contents Expand Table of Contents Return on Investment (ROI) Earnings Per Share (EPS) Price to Earnings (P/E) Ratio Return on Equity (ROE) CAGR The Bottom Line Understanding Key Stock Market Metrics: ROI, EPS, P/E Ratio, and More By Tim Parker Updated September 29, 2025 Reviewed by Chip Stapleton Reviewed by Chip Stapleton Full Bio Chip Stapleton is a Series 7 and Series 66 license holder, CFA Level 1 exam holder, and currently holds a Life, Accident, and Health License in Indiana. He has 8 years experience in finance, from financial planning and wealth management to corporate finance and FP&A. Learn about our Financial Review Board Fact checked by Suzanne Kvilhaug Fact checked by Suzanne Kvilhaug Full Bio See More Suzanne is a content marketer, writer, and fact-checker. She holds a Bachelor of Science in Finance degree from Bridgewater State University and helps develop content strategies. Learn about our editorial policies Close When you purchase a stock, do you use data to drive your decision? Have you ever looked at the fundamental analysis section of a stock's information and found yourself lost? In this article, we will put together some of the most important metrics and explain how to use them to make more informed decisions. Key Takeaways Return on Investment (ROI) measures the profitability of an investment by dividing the return by the cost. However, this metric can be manipulated if certain costs are excluded, so it's crucial to understand the calculation method.Earnings Per Share (EPS) reflects a company's profit per outstanding share, providing insight into financial performance. However, it doesn't account for expenses needed to generate earnings, so it should be evaluated alongside other metrics.The Price-to-Earnings (P/E) Ratio compares a company's current share price to its earnings per share, offering a way to assess a stock's value. A higher P/E may signal an overvalued stock unless justified by strong growth prospects.Return on Equity (ROE) gauges how efficiently a company uses equity to generate profits. By comparing profit to equity investment, ROE highlights operational efficiency, but should be used with additional metrics for a broader picture.Compound Annual Growth Rate (CAGR) calculates the mean annual growth rate of an investment over a period, smoothing out volatile year-to-year returns. This metric supports strategic investment decisions by highlighting consistent long-term performance. Understanding Return on Investment (ROI) Return on Investment (ROI) is simply the money a company has made or lost on an investment. If an individual investor were to invest $1,000 into McDonald's stock and five years later sold it for $2,000, they would have a 100% return on investment or ROI. The return is divided by the cost of the investment to produce the ROI. The problem with this metric is that it's easy to manipulate, as it is also easy to leave costs out of the equation. Before relying on the ROI, understand how it was calculated. Exploring Earnings Per Share (EPS) EPS is a measure of a company's profit. Take the profit, subtract preferred dividends and divide that number by the number of shares outstanding. Although EPS will tell the investor how much money the company is earning per share, it doesn't provide the expense information. If one company made $10 per share and another made $12 per share, the second company's earnings are more impressive only if they spent the same or less money to generate the income. Use EPS in conjunction with other metrics like return on equity. Unpacking the Price-to-Earnings (P/E) Ratio The price-to-earnings ratio (P/E ratio) compares a company's current price to its per-share earnings. The P/E ratio is calculated by dividing the price per share by the earnings per share. This metric is one of the best ways to gauge the value of the stock. If you were planning to purchase a new television, you would probably compare the features and price of multiple televisions. You would expect to pay more for more features. If one TV had fewer features and older technology but cost the same or more than other comparable TVs, that TV may not be a good value. When a stock has a higher P/E ratio than other similar companies, investors may regard the stock as overvalued, unless the company has larger growth prospects or something else that makes the high P/E worth the money. Remember that the actual price of a stock doesn't provide an indication of value. A higher-priced stock could be less valuable when the P/E is examined. Analyzing Return on Equity (ROE) Return on equity (ROE) measures a corporation's profitability. It reveals how efficient a company is at generating profits. To calculate the ROE, divide profit by the amount of equity or the total amount of money invested in the company. If company A had profits of $2 million but had received $1 million of equity, it would be considered more efficient than company B, which also made $2 million but had $1.5 million in equity. Company A is operating more efficiently because they are able to make more money with less investment. ROE should always be used in conjunction with other metrics to evaluate the health and earnings power of a company. Calculating Compound Annual Growth Rate (CAGR) Compound annual growth rate (CAGR) measures the annual growth rate of an investment. For some years may see large gains while other years may return a loss; it could be more helpful to the investor to view their returns as an average over time, rather than year to year. If you had a portfolio of stocks and a few rental properties, after calculating the CAGR, you may increase your investment in the investment type that returns the highest CAGR. The calculation is a little complicated, but you can calculate it here. The Bottom Line Successful investors are well-informed and able to evaluate a company using these and other metrics. Look for these metrics in a stock's fundamental analysis section and decide for yourself whether a company is worth investing in. Take the Next Step to Invest Advertiser Disclosure × The offers that appear in this table are from partnerships from which Investopedia receives compensation. This compensation may impact how and where listings appear. Investopedia does not include all offers available in the marketplace. Read more Investing Markets Stock Markets Partner Links Take the Next Step to Invest Advertiser Disclosure × The offers that appear in this table are from partnerships from which Investopedia receives compensation. This compensation may impact how and where listings appear. Investopedia does not include all offers available in the marketplace.