The 30-scrip sensitive index (Sensex) of the S&P Bombay Stock Exchange (BSE), which opened at 20,766.05 points, was trading at 20,956.61 points in the pre-noon session, up 188.73 points or 0.91 percent from previous day's close at 20,767.88 points.The Sensex touched a high of 21,039.42 points and a low of 20,750.98 points during the trade so far.