The Sensex at the Bombay Stock Exchange declined 88 points, or 0.4 per cent, to 19,663 in opening trade, this morning, as funds and retail investors booked profits, amid weak global markets. Later, the Sensex remained subdued, and stood 99 points, or 0.5 percent in the red, at 19,652 in afternoon trade, a short while ago. The Sensex has lost over 250 points in the past three trading sessions.Stock markets in Japan, Hong Kong, Indonesia, Singapore, Taiwan and South Korea had lost between 0.4 percent and 1.5 percent, today, on profit-booking by investors, after some weak US economic data. The US Dow Jones Industrial Average had ended 0.9 per cent lower in yesterday's trade.