PEG Ratio
P/E ratio divided by earnings growth rate — adjusts P/E for growth.
In depth
PEG below 1.0 traditionally suggests undervaluation; above 1.5 suggests rich valuation. The metric, popularized by Peter Lynch, addresses the limitation that high-growth companies "deserve" higher P/E ratios. Caveat: PEG is highly sensitive to growth-rate assumptions, which often prove optimistic.