The Sensex closed at 16745, down 188 points from its previous close, and the Nifty shut shop at 5032, down 52 points.

Nifty September 2011 futures closed at 5,041.90 at a premium of 9.95 points over spot closing of 5,031.95, while Nifty October 2011 futures were at 5,054.95 at a premium of 23.00 points over spot closing. The near month September 2011 derivatives contract expires on Thursday, September 29, 2011. Nifty September futures saw addition of 6.81% or 1.63 million (mn) units, taking the total outstanding open interest (OI) to 25.59 mn units.

Among Nifty calls, 5100 SP from the September month expiry was the most active call with an addition of 0.64 million or 11.46%. Among Nifty puts, 5000 SP from the September month expiry was the most active put with addition of 0.09million or 1.23%. The maximum Call OI outstanding for Calls was at 5100 SP (6.19 mn) and that for Puts was at 5000 SP (8.11 mn).