Belows the S&P CNX 500 P/E chart since 1996. (Extracted from NSE website http://www.nseindia.com/content/indi..._pepbyield.htm)
This is a very important chart for both technical and fundamental analysts. P/E chart gives indication of when valuations are cheap and when valuations are peaking. This in-turn gives valuable insight on when to Buy and when to Sell.
Discuss your views. Make your own calls what is the best time to buy !