TOKYO (AP) - Japanese business sentiment worsened sharply in the third quarter, a key central bank survey showed Monday, revealing the economy's slide into recession may be accelerating in the wake of the terrorist attacks in the United States. The Bank of Japan's "tankan" survey showed business confidence among executives at large Japanese manufacturers was minus 33, down sharply from minus 16 in the April-June quarter. It was the third straight quarter in which the survey's key indicator has been negative - meaning big-business leaders who have little faith that the economy can emerge from its deepest postwar downturn outnumber those who think the economy is poised to rebound. The latest survey results were somewhat worse than expected. Economists surveyed by Dow Jones Newswires had forecast on average that the index for large manufacturers would read minus 30. The 17-point drop from June marked the third straight quarter of worsening sentiment and the rate of deterioration beat a 15-point decline in March 2001 - the worst since March 1998 when Japan was embroiled in a region-wide financial crisis . The nosedive in sentiment highlighted the beating corporate Japan has taken, as rapid economic downturn, plunging stock prices, slumping exports, and deep uncertainty about the outlook in the aftermath of the assault on the U.S. pummeled the business environment. Concerns about the fallout from the terrorist attacks in the U.S. - Japan's largest export market - likely weighed heavily on corporate minds. The latest tankan, which surveyed companies from late-August to early September, includes replies accepted for more than two weeks after the Sept. 11 attacks, which have caused global economic uncertainty. Major stock markets plummeted as hopes for a U.S. economic recovery this year all but evaporated, while Japanese share prices still linger near 18-year lows. Japan was already in a deep downturn even before the Sept. 11 terror attacks on the World Trade Center in New York and the Pentagon in Washington. Japan's unemployment remained at a record high 5 percent in August, after climbing to that worst level in July since the government began taking statistics in 1953. The Tokyo stock market's main index, the 225-issue Nikkei Stock Average, slumped to its near 18-year low, last month. Faced with a slowing global economy, many Japanese companies have released plans to trim planned investments and production, while announcing job-cuts before the attacks.