Offer your thoughts or opinion on the input financial query or topic using your financial background.

Is forward P/E calculated using current price(if yes, how useful is it)?
P/E can use various estimates in its calculation as one could speculate about future P/E rations and thus could determine a future valuation if one is prepared to say that the P/E should be X for a company. Course it is worth noting that if a company isn't generating positive earnings this can be a less than useful tool, e.g. Amazon in the 1990s lost money every quarter and thus would have had a N/A for a P/E. PEG would use P/E and earnings growth as a way to see if a stock is overvalued based on projected growth. If a company has a high P/E but has a high earnings growth rate then that may prove to be worth it. By using the growth rate, one can get a better idea of the context to that figure. Another way to gain context on P/E would be to look at industry averages that would often be found on Yahoo! Finance and other sites.