A benchmark index of Indian equities markets, the 30-scrip Sensitive Index (Sensex), on Wednesday was trading flat at 8.72 points or 0.03 percent down as auto stocks plunged.The wider 50-scrip Nifty of the National Stock Exchange (NSE) was also trading flat at 2.50 points or 0.03 percent down at 8,831.50 points.The Sensex of the S&P Bombay Stock Exchange (BSE), which opened at 29,087.25 points, was trading at 29,035.72 points (at 9.28 a.m.) in the early session, down 8.72 points or 0.03 percent from the previous day's close at 29,044.44 points.The Sensex touched a high of 29,094.61 points and a low of 28,998.47 points in the trade so far.Good buying was observed in banking and consumer durables sectors, while selling pressure was seen in auto sector.