TOKYO (Kyodo) -- The Tokyo Stock Exchange recently marked one year since it extended its trading hours by 30 minutes, but the prospects for gaining financial industry support for a further extension remain low.

The bourse's operator, Japan Exchange Group Inc., had considered a longer extension but decided against it as businesses are shying away from increasing trading hours due to concerns about additional costs and workloads.

While the TSE lags behind major bourses overseas in terms of trading hours, analysts said the benefit of the 30 minute, or 10 percent, extension was limited.

The bourse's operator estimates that the extension increased trading value by around 5 percent.

Prior to the extension, trading hours totaled five hours, from 9:00 a.m. to 11:30 a.m. and from 12:30 p.m. to 3:00 p.m. The close of trading was changed to 3:30 p.m. on Nov. 5 last year.

"If Japan aims to become a leading country in asset management, building the capital market to match the global standard is essential," said Takashi Hiroki, chief strategist at Monex Inc., suggesting a much bigger extension is desirable at a time when U.S. stock markets are shifting toward a future of around-the-clock trading.

However, the TSE is apparently not convinced that longer hours will bring a large enough increase in trading volume to offset higher costs and a greater burden on staff.

"We have not started considering (a further extension) yet," Hiromi Yamaji, the CEO of Japan Exchange Group, told a press conference late last month.