Japan's Nikkei 225 stock index sinks nearly 13% as investors dump a wide range of shares

Japan’s Nikkei 225 share index plunged nearly 13% as investors worried that the U.S. economy may be in worse shape than had been expected dumped a wide range of shares.

The Nikkei index was down 12.9% at 31,290.63 by midafternoon Monday in Tokyo .

It dropped 5.8% on Friday and it is headed for its worst two-day decline ever.

The Nikkei's biggest single-day rout was a plunge of 3,836 points, or 14.9%, on the day dubbed “Black Monday” in October 1987. It suffered an 11.4% drop in October 2008 during the global financial crisis and fell 10.6% during the aftermath of massive earthquakes and nuclear meltdowns in northeastern Japan in March 2011.

Share prices have fallen in Tokyo since the Bank of Japan raised its benchmark interest rate on Wednesday. The benchmark is now about 4% below the level it was at a year ago.

The wave of selling hit a broad range of companies.

Toyota Motor Corp.'s shares dropped 11% and Honda Motor Co. lost 13.4%. Computer chip maker Tokyo Electron dived 15.8% and Mitsubishi UFJ Financial Group plunged 18.4%.