The Sensex at the Bombay Stock Exchange declined 192 points, or 1.1 percent, to 17,509, today, amid weak global markets. The Nifty at the National Stock Exchange fell 61 points, or 1.2 percent, to 5,251. Global markets also lost ground, with the bourses in Japan, China, South Korea and Singapore losing between 0.5 percent and 2 percent.The markets fell after Chinese manufacturing growth slowed, and Moody's Investors Service placed Spain's credit rating on review for a possible downgrade, fueling concern over the strength of the global economic recovery.