Definition of PEG
PEG of Facebook, Inc.
The PEG ratio is calculated by dividing the P/E ratio by the company's expected earnings growth rate in the next 5 years. Since using just the P/E ratio would make high-growth companies appear overvalued relative to others, the PEG ratio is considered to be a convenient approximation. PEG is a widely employed indicator of a stock's possible true value.
Similar to P/E ratios, a lower PEG means that the stock is undervalued more. It is favored by many over the price/earnings ratio because it also accounts for growth. The PEG ratio of 1 is sometimes said to represent a fair trade-off between the values of cost and the values of growth, indicating that a stock is reasonably valued given the expected growth. A crude analysis suggests that companies with PEG values between 0 and 1 may provide higher returns. A PEG Ratio can also be a negative number if a stock's present income figure is negative, (negative earnings) or if future earnings are expected to drop (negative growth). PEG ratios calculated from negative present earnings are viewed with skepticism as almost meaningless, other than as an indication of high investment risk.