The Nifty 50 index needs to sustain above the 23,800 level and thereafter, the significant 200 period MA of 23,920 level to improve the bias, says expert.

TCS results will give an indication of what is in store for the IT sector. The strength of the US economy and the depreciation of rupee will be tailwinds for the IT sector.

Around 11:05 am, Sensex was trading 448.21 points lower at 77,700.28 and Nifty was down 142.85 points to 23,546.10