Unrealized profits on shares held by the top four Japanese life insurance companies are expected to total some 12 trillion yen at the Friday end of fiscal 2005, double last year's figure, according to an estimate based on the Tuesday close of the Nikkei stock average.

The sharp increase in latent profit owes to a jump of more than 40 percent in the Tokyo stock market over the past year, thanks to Japan's economic recovery. The 225-issue Nikkei average closed at 16,690.24 Tuesday.

To date, latent profits averaged 5.75 trillion yen at Nippon Life Insurance Co., a twofold increase from a year earlier; 3 trillion yen at Dai-ichi Mutual Life Insurance Co., up 2.5-fold; 2.5 trillion yen at Meiji Yasuda Life Insurance Co., also up 2.5-fold; and 900 billion yen at Sumitomo Life Insurance Co., a more than threefold rise.

While life insurers have been building up retained profits, the increase in unrealized profit will enable them to "pass greater profits on to policyholders and carry out strategic investments," an executive at one of the top firms said.