Falling for the fourth straight session, the Sensex at the Bombay Stock Exchange lost 89 points, or 0.6 percent, to close at 15,455, on the last trading session of 2011, on Friday, amid continued FII outflows. The Sensex had already lost more than 425 points in the previous three trading sessions. The Nifty at the National Stock Exchange slipped 22 points, or 0.5 percent, to 4,624. Stock markets in Japan, China, and Hong Kong rose between 0.2 percent and 1.2 percent.