Administrators of failed insurer Chiyoda Mutual Life Insurance Co. said Friday that they are close to determining the firm's negative net worth -- somewhere around 311.9 billion yen -- and that the final figure will be released by the end of the month.

Chiyoda Mutual, which went bust in October, is scheduled to make a fresh start in April as AIG Star Life Insurance Co., under the sponsorship of American International Group Inc.

The failed insurer's negative net worth, or excess of liabilities over assets, was previously estimated at 600 billion yen. This figure was reduced, however, after the insurer tapped its policy reserves and sold some assets, the administrators said.

The guaranteed rates of return on existing policies will be cut to an average 1.5 percent, while benefits on life insurance policies and annuities will also be reduced, they said.

As part of its sale of assets, Chiyoda Mutual sold the site of the now-closed Hotel New Japan in central Tokyo -- along with a high-rise building the insurer was constructing on the site -- to the Prudential Group of the United States. The site had been held by a unit of Chiyoda, while the building consists of offices, housing and commercial facilities.

The value of the sale was not disclosed.