The BSE Sensex declined for a fifth consecutive session on Friday, tumbling by nearly 660 points to drop below the 80,000 level, driven by extensive selling pressure, significant foreign capital outflows, and muted earnings growth. According to PTI, the Sensex fell 662.87 points, or 0.83 per cent, closing at 79,402.29. During the day, it reached an intraday low of 79,137.98, reflecting a deeper plunge of 927.18 points, or 1.15 per cent.