The Sensex at the Bombay Stock Exchange opened 72 points, or 0.4 per cent higher, at 16,932, this morning, on continued buying by funds and retail investors, amid firm Asian markets. But later, in afternoon trade, the Sensex turned very volatile, and after slipping briefly into the red, again moved up, to stand 32 points, or 0.2 percent in the positive zone, at 16,8,92 a short while ago. Meanwhile, global rating agency, Fitch has cut the rating outlook of 11 India-based financial institutions, including State Bank of India, ICICI Bank, and Punjab National Bank, to negative.Key stock indices in Japan, Singapore, Taiwan, South Korea, Hong Kong and Indonesia were up by between 0.5 percent and 1.2 percent, today, on hopes of more monetary easing by the US central bank. The US Dow Jones Industrial Average had ended 0.8 per cent higher in yesterday's trade.