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When to buy shares - 6 key figures

Company performance ratios to help you assess company potential

Financial ratios can be incredibly useful for deciding whether and when to buy shares. You can view them on our company overview pages or in annual reports; but what do they mean?

1. Dividend yield

Dividend yield reflects how much income investors receive for each pound invested, but it should not be considered in isolation.

A low dividend yield could indicate a high share price, due to positive growth prospects, or it could mean the company can’t afford to pay a decent dividend. Conversely, a high dividend yield may lessen the impact of any fall in share price, but it could raise concerns over prospects and affordability of the dividend in future.

Dividend yield = Net dividend income per share / Market share price

2. Dividend cover

Dividend cover reflects the number of times a company’s profit covers the ordinary dividend. Generally, a ratio of 2 or higher is considered safe, with anything below 1.5 being risky.

At 1, a company’s profits are only just covering dividends. Under 1 means dividends are being paid from retained earnings, which is not normally sustainable.

Dividend cover = Net earnings per share / Net dividend per share

3. Price/earnings (P/E) ratio

The P/E ratio reflects the price investors are prepared to pay for each pound of company earnings. A high ratio indicates that the market expects future earnings to grow quicker than at a company with a low P/E. It should be used to compare with historical performance or companies in the same industry.

P/E ratio = Market share price / Earnings per share

4. Price/earnings to growth (PEG) ratio

The price/earnings to growth ratio (PEG ratio) is seen as a better investment tool than the P/E ratio because it considers future growth, in addition to historical performance.

Shares with a PEG of 1 or lower are considered good value (the lower the PEG, the less you pay for estimated future earnings). However, it is only as reliable as the estimated growth forecast.

PEG ratio = P/E ratio / Estimated future growth

5. Gearing ratio

Gearing reflects to what extent a company is encumbered with debt. Anything over 100 is considered risky, but it varies between industries. 

Gearing ratio = A company’s debt / Market Capitalisation

6. Price-to-book (PB) ratio

The price-to-book ratio can be a useful tool for finding undervalued companies. Anything under 2 is considered good value, while over 2 implies it may be overpriced. It relies on the valuation of assets being accurate and current.

P/B ratio = Market share price / Net asset book value per share

Read more about how to value and assess prospects of an investment

These articles are provided for information purposes only. The content is not intended to be a personal recommendation. The value of your investments, and the income derived from them, may go down as well as up. If in doubt, please seek advice from a qualified investment adviser.