NEW YORK (AP) _ Salomon Inc., which reported its first-ever annual loss early this month, acknowledged Monday that the results were even worse because of yet another bookkeeping blunder by the big Wall Street investment firm.

The parent of Salomon Brothers Inc. said it was revamping the financial and operations staff as a result of the latest undetected error and was reassessing the performance of its outside auditor.

Arthur Anderson & Co., the company's main outside auditor, didn't immediately return a phone call for comment.

Salomon revised upward its 1994 loss to $399 million from the $364 million reported early this month.

For the fourth quarter, Salomon actually lost $157 million. The previously reported deficit was $122 million.

Salomon said the new figures include a $35 million after-tax charge for a previously undetected error in recording a 1988 transaction involving Japanese yen. The charge was on top of a $126 million charge that Salomon reported early this month, when it blamed bookkeeping discrepencies in its London-based business and U.S. operations.

The parent firm's stock was down 87 1/2 cents per share to $35.87 1/2 by late afternoon.

``Hopefully it's all over with,'' said Perrin Long, a securities industry analyst with Brown Brothers Harriman & Co.

``They were honest to admit and come out and say upon further checking ... they found additional losses and they have to take more charges,'' Long said.

The latest charge brought Salomon's loss for the fourth quarter to $1.65 per share. Salomon previously said it lost $1.32 per share in the period.

That compared with Salomon's profit of $4.33 per share in 1993's fourth quarter.

For the year, Salomon revised upward its loss to $4.31 per share. Salomon previously said it lost $3.98 per share.

For all of 1993, Salomon earned $827 million, or $7.01 per share.

Revenues were also revised downward. Salomon said total 1994 revenues were $6.28 billion, compared to the previously reported $6.34 billion. Salomon's revenues were $8.80 billion in 1993.

For the fourth quarter, total revenues were $1.53 billion. compared to the previously reported $1.59 billion. In 1993's final quarter, Salomon's revenues were $2.76 billion.

Salomon also disclosed another revision that it said had no impact on total revenues or net income. It reclassified revenues previously attributed to principal transactions as revenues from interest and dividends.

The change increased interest and revenues by $328 million in 1994 and $182 million in 1993, while decreasing principal transaction revenues by the same amounts for those years.

Salomon blamed a computer glitch that failed to distinguish between interest income and principal gains and losses when the firm redeemed foreign securities, mostly short-term Mexican government debt securities known as Mexican Tesobonos and Cetes.