Finance Learning - P/E ratio

Price Earning Ratio

P/E, you simply take the current stock price of a company and divide by its earnings per share (EPS):
Most of the time, the P/E is calculated using EPS from the last four quarters.

Historically, the average P/E ratio in the market has been around 15-25. This fluctuates significantly depending on economic conditions. The P/E can also vary widely between different companies and industries.

In other words, a P/E ratio of 20 suggests that investors in the stock are willing to pay $20 for every $1 of earnings that the company generates. However, this is a far too simplistic way of viewing the P/E because it fails to take into account the company's growth prospects.

Although the EPS figure in the P/E is usually based on earnings from the last four quarters, the P/E is more than a measure of a company's past performance. It also takes into account market expectations for a company's growth. Remember, stock prices reflect what investors think a company will be worth. Future growth is already accounted for in the stock price. As a result, a better way of interpreting the P/E ratio is as a reflection of the market's optimism concerning a company's growth prospects.

The P/E ratio is a much better indicator of the value of a stock than the market price alone. For example, all things being equal, a $10 stock with a P/E of 75 is much more "expensive" than a $100 stock with a P/E of 20. That being said, there are limits to this form of analysis - you can't just compare the P/Es of two different companies to determine which is a better value.

1. Company growth rates - How fast has the company been growing in the past, and are these rates expected to increase, or at least continue, in the future? Something isn't right if a company has only grown at 5% in the past and still has a stratospheric P/E. If projected growth rates don't justify the P/E, then a stock might be overpriced. In this situation, all you have to do is calculate the P/E using projected EPS.

2. Industry - It is only useful to compare companies if they are in the same industry. For example, utilities typically have low multiples because they are low growth, stable industries. In contrast, the technology industry is characterized by phenomenal growth rates and constant change. Comparing a tech company to a utility is useless. You should only compare high-growth companies to others in the same industry, or to the industry average.

Earnings is an accounting figure that includes non-cash items. To complicate matters, EPS can be twisted, prodded and squeezed into various numbers depending on how you do the books. The result is that we often don't know whether we are comparing the same figures, or apples to oranges.

A low P/E ratio does not necessarily mean that a company is undervalued. Rather, it could mean that the market believes the company is headed for trouble in the near future. Stocks that go down usually do so for a reason. It may be that a company has warned that earnings will come in lower than expected. This wouldn't be reflected in a trailing P/E ratio until earnings are actually released, during which time the company might look undervalued.

First of all, we believe that novice investors shouldn't be shorting. Secondly, you can get into a lot of trouble by valuing stocks using only simple indicators such as the P/E ratio. Although a high P/E ratio could mean that a stock is overvalued, there is no guarantee that it will come back down anytime soon. On the flip side, even if a stock is undervalued, it could take years for the market to value it in the proper way.