I really don't know. One of the reasons I don't use the general P/C ratio but the equity P/C ratio is that these indices and the futures on indices are used in various hedging tactics, thus I have not found these good predictor of future markets.When puts on the DJX gets excessive (five to ten times the call volume), I tried to see if it indicates a future market turn, and the short study did about 18 months ago indicated only a 60% chance that after such an excess put buying in indices, the market turn up, almost as often as not it continued it merry ways down...Thus, I have no idea if the trin on those indices "stocks" has any predictive power. It does not work, so I don't use it.
Zeev
Market Data 
Markets 
AI
