Jan. 28 (Bloomberg) -- One of Wall Street’s biggest bears is leaving Morgan Stanley after a year and a half on the job.

Abhijit Chakrabortti resigned yesterday as the New York- based bank’s chief global and U.S. equity strategist, spokeswoman Carissa Ramirez said. No reason was given for the departure, which came 17 months after he moved from JPMorgan Chase & Co. Chakrabortti couldn’t be reached for comment.

His 2008 prediction for the Standard & Poor’s 500 Index was the most accurate on Wall Street and still missed by 622 points. Chakrabortti predicted the benchmark gauge would finish last year at 1,525, a projection that proved too high after $1 trillion of bank losses sent stocks to their worst year since the Great Depression. He said U.S. banks were fairly valued in November before they fell an average 29 percent.

In the two years before coming to Morgan Stanley, Chakrabortti, 41, was the most bearish forecaster among strategists tracked by Bloomberg. He predicted the S&P 500 would drop 9.9 percent in 2006 and gain 1.5 percent in 2007. The index climbed 14 percent and 3.5 percent, making his call the most prescient of 2007.

“I’m going to miss his research,” said Guillermo Araoz, director of equity analysis at Morgan Asset Management, which oversees $30 billion in Birmingham, Alabama. “He was in the top- tier of equity strategists on Wall Street.”

The S&P 500 added 3.4 percent to 874.09 today.

Rally This Year

Chakrabortti’s year-end S&P 500 estimate for 2009 of 975, a 15 percent gain from yesterday’s close, was tied for the second- lowest among 10 strategists tracked by Bloomberg. He said stocks would rise this year because of cheap valuations and “compelling” dividends, according to a Nov. 25 note to clients.

On Nov. 17, Chakrabortti said investors in U.S. bank stocks were ignoring an improvement in credit markets and the financial sector was “fairly valued to moderately cheap.” He recommended Wells Fargo & Co., JPMorgan Chase & Co., PNC Financial Services, Bank of New York Mellon Corp. and State Street Corp.

The KBW Bank Index tumbled 29 percent since then, and only Bank of New York advanced. PNC fell the most, losing 37 percent.

Chakrabortti said at the time that if “credit and money markets were to again deteriorate, then the current BKX level could be justified,” referring to the 24-company KBW index’s ticker symbol.

Chakrabortti joins Byron Wien, who works at hedge fund Pequot Capital Management Inc., and Barton Biggs, who runs Traxis Partners LLC, in the ranks of former Morgan Stanley strategists.

Morgan Stanley dropped to 10th from ninth place in Institutional Investor magazine’s 2008 survey of the top equity research firms.

To contact the reporter on this story: Lynn Thomasson in New York at lthomasson@bloomberg.net.

Last Updated: January 28, 2009 16:13 EST