The Price to Earnings to Growth (PEG) Ratio helps to determine a more accurate value of a stock by looking at the current PE Ratio and factoring its' expected earnings growth rate over a specified time frame.
PEG Ratio = PE Ratio / EPS Growth
Let's say Disney's P/E Ratio is 15.98 and has a forecasted EPS of $0.83 for the current earnings period, as a result Disney would have a a PEG Ratio of 19.25.
The The PEG ratio is considered to be an indicator of a stock's true value, and similar to the P/E ratio, a lower PEG may indicate that a stock is undervalued. - Investopedia