Falling for the sixth straight session, the Sensex at the Bombay Stock Exchange dropped 209 points, or 1 percent, to close at a one-month low of 20,282, on tuesday, on rupee weakness, and ahead of industrial output and retail inflation data. The Sensex has now lost over 950 points in six trading sessions. The Nifty at the National Stock Exchange fell 61 points, or 1 percent, to 6,018.Stock markets in Japan, China, Hong Kong, South Korea and Singapore ended mixed.