The Sensex, which opened 221 points down on Monday is now trading 270 points down at 19,422 points. Sensex trading in negative zone as funds and retail investors continued selling on fears of another hike in key interest rates by the RBI to reign in inflation. The 30-share index of the Bombay Stock Exchange tumbled 868 points in the previous four sessions. In a similar fashion, the broad-based National Stock Exchange index Nifty fell by 80 points form earlier opening in the red of 71 points at 5,833 points.